ACTIVITATS FORMATIVES · Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the ... Supramolecular Chemistry: Concepts and Perspectives, VCH

ACTIVITATS FORMATIVES

Sala d'ActesFacultat de Ciències i BiociènciesFacultat de Ciències i Biociències

Universitat Autònoma de Barcelona

Activitat Formativa del Doctorat en Química

Programa de Doctorat distingit amb Menció cap a l'Excel∙lència pel Ministerio de EducaciónNº MEE2011‐0466 (Cursos 2011/12 ‐ 2012/13 ‐ 2013/14)

de DOCTORAT en QUÍMICA

JORNADES DOCTORALS – 2012

JUNE 6 to 8, 2012

WELCOME TO JORNADES DOCTORALS-2012 !!!!

It is our great pleasure to organize the "Segona Edició de les Jornades Doctorals“, as you know this event aims to relate the chemical research performed by the PhD students of the UAB Chemistry PhD program, and related programs, with Industrial and Entrepreneurship Opportunities. In its second edition, the “Jornades Doctorals” will include an exciting series of conferences of 3rd - 4th year UAB-Chemistry PhD students, and three academic experts in different chemistry fields:

-Wednesday, 6 June 2012: Prof. Jean-Marie Lehn, Chemistry Nobel Laureate in 1987 for "for their development and use of molecules with structure-specific interactions of high selectivity".

-Thursday, 7 June 2012: Prof. Benjamin G. Davis, Tetrahedron Young Investigator Award for Bioorganic and Medicinal Chemistry (2012).

- Friday, 8 June 2012: Prof. Javier García Martínez, Professor at the University of Alicante, co-founder Rive Technology Inc and Vice-chair of the World Economic Forum General Assembly Council on Emerging Technologies.

We look forward to your participation in this event.

The Organizing Committee

Organizing, Scientific and Prizes Committee

Prof. Gonzalo Guirado López, PhD Coordinator of the studies in Chemistry and President of the Chemistry PhD Committee (UAB).

Prof. Rosa Maria Ortuño Mingarro, Master Coordinator of the studies in Chemistry and President of the Chemistry Master Committee (UAB).

Prof. Jordi García-Antón Avinyó, Secretary of PhD and Master Studies Committee (UAB).

Prof. Félix Busqué Sánchez, Vocal of PhD and Master Studies Committee (UAB).

Prof. José Peral Pérez, Vocal of PhD and Master Studies Committee (UAB).

Prof. María Isabel Pividori Gurgo, Vocal of PhD and Master Studies Committee (UAB).

Prof. Gregori Ujaque Pérez, organizer of the UAB Cycle Chemistry Conferences.

Chemistry Department Administrative Support:

Toñi Romero Prieto, Administrative Assistant PhD Studies in Chemistry.

Event Sponsored By: Estudi de Doctorat en Química – Departament de Química

JORNADES DOCTORALS 2012 SCIENTIFIC PROGRAM

June 6, 2012

10.00-10.30 h – Opening Ceremony

Prof. Manel López Bejar, Vicerector of Research, UAB.

Prof. Jordi Bartrolí Molins, Dean of the Faculty of Sciences, UAB.

Prof. Jordi Marquet Cortés, General Director of the UAB Research Park.

Prof. Josep Maria Lluch López, Director of the Department of Chemistry, UAB.

Prof. Gonzalo Guirado López, PhD Coordinator of the studies in Chemistry, UAB.

10.30-11.30 h – Jornades Doctorals Lecture

Chairman: Prof. J. Font

Perspectives in Chemistry: From Supramolecular Chemistry towards Adaptive Chemistry Professor Jean Marie Lehn

11.30-13.00 h - Coffee Break and Poster Session

June 7, 2012

09.30-11.00 h - Flash Presentations I

Chairwoman: Prof. M.I. Pividori

09.30-09.45 h – Immunochemical strategies based on magnetic beads for clinical diagnosis and food safety - Tamara Laube Chávez (FP1-1)

09.45-10.00 h – Heterogeneous Ruthenium WOC’s - Joan Aguiló Carreras (FP1-2)

10.00-10.15 h – Photoluminescence properties in novel molecular and dendrimeric boron containing systems. The key role of the carboranyl substiuents - Albert Ferrer Ugalde (FP1-3)

10.15-10.30 h – On the role of solvents in the performance of inkjet printed organic solar cells - Ignasi Burgués Ceballos (FP1-4)

10.30-10.45 h – Synthesis of new nanoscale MOFs for contrast agent applications - Arnau Carné Sánchez (FP1-5)

10.45-11.00 h – Cyclobutane containing mixed peptides: folding and gelation properties - Sergi Celis Rodríguez (FP1-6)

11.00-11.30 h – Break

11.30-13.00 h - Flash Presentations II

Chairman: Prof. G. Ujaque

11.30-11.45 h – The application of cork in the removal of heavy metals from aqueous solutions - Enrique R. Navarrete Hernández (FP2-1)

11.45-12.00 h – Synthetic microengines for environmental and sensing purposes - Maria Guix Noguera (FP2-2)

12.00-12.15 h – New bioconjugated rhenium and technetium carbonyls by transmetallation reaction with zinc derivatives - Joan Lecina Vicente (FP2-3)

12.15-12.30 h – Study of Kinetics and Mechanisms of Liquid Phase Photocatalytic Reactions with Titanium Dioxide (TiO2) - Juan F. Montoya Arango (FP2-4)

12.30-12.45 h – Diversity Oriented and Enantioselective Synthesis of Gabosines and Anhydrogabosines - Miguel A. Fresneda Quesada (FP2-5)

12.45-13.00 h – Development of electronic tongue for simultaneous determination of heavy metals in soil samples and monitoring of biosorption processes - Deivy Wilson Massó (FP2-6)

13.00-15.00 h – Break

15.00-16.30 h – Flash Presentations III

Chairman: Prof. J. Peral

15.00-15.15 h – Stepwise sequential redox potential modulation possible on a single platform - Màrius Valentin Lupu (FP3-1)

15.15-15.30 h – Computational Analysis on the Mechanism of Homogeneous Gold-catalyzed Reactions - Sergi Montserrat Gironés (FP3-2)

15.30-15.45 h – Molecular modeling role in the design of new artificial metalloenzymes - Víctor Muñoz Robles (FP3-3)

15.45-16.00 h – Palladium Nanoparticles in catalysis: Tapping into the Potential of Tris-Imidazolium Salts for Nanoparticle Stabilization - Marc Planellas Oates (FP3-4)

16.00-16.15 h – New derivatives of 1,1’-binaphthalene in the field of chiral recognition: enantiodifferentiation and enantioselective synthesis - Josep Recasens Bonet (FP3-5)

16.15-16.30 h – Influential Role of Ethereal Solvent on Organolithium Compounds: the Case of Carboranyllithium - Ana Daniela Musteti (FP3-6)

16.30-17.00 h – Break


Chairwoman: Prof. R.M. Ortuño

Sugars & proteins Professor Benjamin G. Davis

June 8, 2012

09.30-11.00 h - Flash Presentations IV

Chairman: Prof. F. Busqué

09.30-09.45 h – Preparation of micro and nanoparticulate materials using microemulsions with CO2-expanded solvents - Paula E. Rojas Labanda (FP4-1)

09.45-10.00 h – Metallothioneins as detoxifying agents for pb(ii) - Catalina T. Pérez Zúñiga (FP4-2)

10.00-10.15 h – Synthesis and characterization of Goethite nanorods. TEM study of the phase change from Goethite to Hematite - Leonardo Pérez Mirabet (FP4-3)

10.15-10.30 h – Fluorescent molecular switches: an electrochemical approach - Gemma Prats Álvarez (FP4-4)

10.30-10.45 h – Synthesis of new binaphthalenic C2-symmetry molecules with stereogenic axis and centers - Marta Sangüesa Amorós (FP4-5)

10.45-11.00 h – Photochromic nanocomposites as photoprotective coatings - Nuria A. Vázquez Mera (FP4-6)

11.00-11.15 h - Break

11.15-12.00 h - Flash Presentations V

Chairman: Prof. J. García- Antón

11.15-11.30 h – Sulfonated Phosphines with Strong Electrowithdrawing Substituents for Biphasic Hydroformylation of Polar Alkenes - Daniel Peral Crespo (FP5-1)

11.30-11.45 h – Mechanisms of olefin metathesis: reactivity and efficiency in the precursor activation and productive catalytic cycles - Francisco Núñez Zarur (FP5-2)

11.45-12.00 h – High sensitive lateral flow device for cadmium determination - Adaris M. López Marzo (FP5-3)

12.00-12.30 h - Break


Chairman: Prof. G. Guirado

Nanotechnology’s next challenge: Commercialization

Professor Javier García Martínez

13.30-14.00 h – Award and closing ceremony

Jornades Doctorals 2012 Awards

Jornades Doctorals -2012 distinguished Diploma, along with an iPad, will be given for the two best Poster-Flash Presentations.

JORNADES DOCTORALS 2012

LECTURES

JORNADES DOCTORALS 2012 1

Perspectives in Chemistry: From Supramolecular Chemistry towards Adaptive Chemistry

Jean-Marie LEHN, Orga ISIS, Université de Strasbourg, France,

E-mail: [email protected]

Supramolecular chemistry is actively exploring systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, on the basis of the molecular information stored in the covalent framework of the components and read out at the supramolecular level through specific non-covalent interactional algorithms, thus behaving as programmed chemical systems. The design of molecular information controlled, “programmed” and functional self-organizing systems provides an original approach to nanoscience and nanotechnology. The spontaneous but controlled generation of well-defined, functional molecular and supramolecular architectures of nanometric size through self-organization represents a means of performing programmed engineering and processing of functional nanostructures. It offers a very powerful alternative to nanofabrication and to nanomanipulation for the development of nanotechnology. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their components. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels. CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation. Applications of this approach in biological systems as well as in materials science will be described. The merging of the features: - information and programmability, - dynamics and structural diversity, -constitution and selection, points towards the emergence of adaptive and evolutive chemistry. References [1] J.-M. Lehn, Supramolecular Chemistry: Concepts and Perspectives, VCH Weinheim, 1995. [2] J.-M. Lehn, Dynamic combinatorial chemistry and virtual combinatorial libraries, Chem. Eur. J., 1999, 5, 2455. [3] J.-M. Lehn, Programmed chemical systems : Multiple subprograms and multiple processing/expression of molecular information, Chem. Eur. J., 2000, 6, 2097. [4] J.-M. Lehn, Toward complex matter: Supramolecular chemistry and self-organization, Proc. Natl. Acad. Sci. USA, 2002, 99, 4763. [5] J.-M. Lehn, Toward self-organization and complex matter, Science, 2002, 295, 2400. [6] J.-M. Lehn, From supramolecular chemistry towards constitutional dynamic chemistry and adaptive chemistry, Chem. Soc. Rev., 2007, 36, 151


Sugars & proteins Benjamin G. Davis

Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK

E-mail: [email protected] Sugars and Post-Translational Modifications are critical biological markers that modulate the properties of Proteins. Our work studies the interplay of proteins, sugars and modifications. This lecture will cover emerging areas in our group in (a) biomolecule construction with an em-phasis on new bond-forming processes compatible with biology (Topics (i), (ii)) and (b) use of chemical probes & modulators of carbohydrate & protein processing events (Topic (iii)). (i) Synthetic Biology’s development at the start of this century may be compared with Synthetic Organic Chemistry’s expansion at the start of the last; after decades of isolation, identification, analysis and functional confirmation the future logical and free-ranging redesign of biomacro-molecules offers tantalizing opportunities. New methods are required[1-8]: despite 80-years-worth of non-specific, chemical modification of proteins, precise methods in protein chemistry remain rare. The development of efficient, complete, chemo- & regio-selective methods, ap-plied in benign aqueous systems to redesign the structure and function of proteins will be pre-sented. (ii) ‘Synthetic Biologics’ and their applications[3,9-13]: drug delivery; selective protein degra-dation; nanomolar inhibitors of bacterial interactions; gene delivery vehicles; probes of in vivo function; non-invasive pre-symptopmatic disease diagnosis; targeted high intensity radioprobes; designed glycoconjugate vaccines. (iii) Chemical Probes and Modulators: Delineation of mechanisms of carbohydrate- and protein-processing systems and their ligands allows not only an understanding of their fundamental role in Biology and Immunology but also the use of molecules to modulate and manipulate such proc-esses, with a strong associated potential for diagnosis, therapy and intervention.[14,15,16]

[1] B.G. Davis, Chem. Rev. 2002, 102, 579-601; D.P. Gamblin et al. Chem. Rev. 2009, 109, 131-163 [2] B.G. Davis, Science 2004, 303, 480-482 [3] S.I. van Kasteren et al. Nature 2007, 446, 1105-1109. [4] S.I. van Kasteren et al. Nat. Protoc. 2007, 2, 3185-3194 [5] G.J.L. Bernardes et al. Angew. Chem. Int. Ed. 2008, 47, 2244-2247 [6] G.J.L. Bernardes et al. J. Am. Chem. Soc. 2008, 130, 5052-5053 [7] Y.A. Lin et al. J. Am. Chem. Soc. 2008, 130, 9642-9643 [8] J.M. Chalker et al. J. Am. Chem. Soc. 2009, 131, 16346-16347. [9] M.A. Robinson et al. Proc. Natl. Acad. Sci. USA 2004, 101, 14527-14532 [10] C. Fleming et al. Nat. Chem. Biol. 2005, 1, 270-274 [11] S.I. van Kasteren et al. Proc. Natl Acad. Sci. U.S.A. 2009, 106, 18-23 [12] S.Y Hong et al. Nat. Materials 2010, 9, 485-490 [13] K.J. Doores et al. Proc. Natl. Acad. Sci. USA 2010, 107, 17107-17112 [14] E.J. Cocinero et al, Nature, 2011, 469, 76-79. [15] K.M. Backus et al. Nat. Chem. Biol. 2011, 7, 228-235 [16] S. Seo Lee et al. Nat. Chem. Biol. 2011, 7, 631-638


Nanotechnology’s next challenge: Commercialization Javier García Martínez

Inorganic Chemistry and the director of the Nanotechnology Molecular Laboratory at the University of

Alicante, Spain E-mail: [email protected]

After the discovery of the foundations of nanotechnology such as electron and scanning tunne-ling microscopy, carbon nanotubes and fullerenes in the last decades of the twentieth century, governments in industrialized countries created specific programs for the development of nano-technology. This public investment has been followed by venture capital and the R & D depart-ments of large companies, which saw the exponential growth in the number of nanotechnology patents as an indicator of its potential. However, despite the numerous and exciting discoveries in nanotechnology, its greatest challenge is still to realize its full potential. During the lecture, we will analyze some of the barriers to be overcome in order to transform this emerging tech-nology into a new industry such as: technology transfer, promoting entrepreneurship in nano-technology research centers, intellectual property protection and funding of new nanotechnolo-gy start-ups with adequate venture capital funds. Finally, Javier Garcia will talk about his expe-rience as an entrepreneur, founder of the nanotechnology start-up Rive Technology and his work as vice-chairman of the council on Emerging Technologies of the World Economic Forum to iden-tify, raise awareness and promote technologies able to produce new industries, create jobs and improve the competitiveness of our economy.


FLASH PRESENTATIONS I


Immunochemical strategies based on magnetic beads for clinical diagnosis and food safety

Tamara Laube, Salvador Alegret, Maria Isabel Pividori

Grup de Sensors i Biosensors, Departament de Química, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. [email protected]

Abstract The detection of infectious diseases as well as food contaminants are both important issues in public health. In the case of endemic diseases affecting developing countries there is an urgent need for improved diagnostic tools that can be used at community and primary care level, while in food safety fast and on site testing of incoming raw materials as well as contamination monitoring during the industrial processing is mandatory. The development of biosensors is a growing area in response to these demands, and offers a promising alternative to the more traditional analytical methods, allowing rapid ‘real-time’, selective and low cost analyses [1]. Particularly, immunosensors are promising alternatives to the existing immunochemical tests and magnetic beads have brought novel capabilities to electrochemical immunosensing. Moreover, magnetic beads are known to be a powerful and versatile tool in a variety of analytical and biotechnological applications and provide great improvements for immunoassays based on the concept of magnetic bioseparation while minimizing matrix effect [2]. In this work, the development of immunological strategies on magnetic beads for different applications is presented: i) for clinical diagnoses, the quantification of a specific biomarker related to the rapid diagnosis of Malaria [3], and ii) for food safety, the detection of gliadin in gluten-free foodstuff [4], and pathogenic bacteria (like Salmonella). Depending on the target, different immunoassay formats have been used (competitive or sandwich, direct or indirect) and also different kinds of beads to which the desired biomolecules have been covalently immobilized. In all cases, the results were evaluated using optical detection through a magneto-ELISA, and electrochemical detection through a magneto-sensor and the signal was obtained by a peroxidase conjugate as the enzymatic label. Matrix effect as well as the performance of the assays was successfully evaluated using spiked samples, achieving excellent LOD and recovery values. All strategies show great promise for rapid, simple, cost-effective and on-site analysis of samples. References [1] S. Alegret, M.I. Pividori, Alegret and Merkoçi Ed., Comprehensive Analytical Chemistry, 2007, 49, Elsevier B.V., Chapter 22. [2] E. Zacco, M.I. Pividori, S. Alegret, Anal. Chem., 2006, 78, 1780. [3] M. De Souza Castilho, T. Laube, H. Yamanaka, S. Alegret, M.I. Pividori, Anal. Chem. 2011, 83, 5570. [4] T. Laube, S.V. Kergaravat, S.N. Fabiano, S.R. Hernández, S. Alegret, M.I. Pividori, Biosens. Bioelectron. 2011, 27, 46.

REF: FP1‐1


Heterogeneous Ruthenium WOC’s

Joan Aguiló, Lluís Escriche, Xavier Sala Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain, [email protected]

Abstract The understanding of the water oxidation reaction to molecular oxygen is still one of the great challenges faced by scientific community. Mononuclear and dinuclear Ru complexes have been recently studied by ourselves and by other groups1, and have become a very useful platform for mechanistic studies2. The anchoring of these molecular catalysts into solid supports is the next step to demonstrate the viability of building a device that coupled to proton reduction would lead to water splitting. Immobilization of molecular water oxidation catalysts onto metal oxides such as TiO2, SiO2, ITO or FTO as well as into carbon surfaces are some of the strategies that have been used3. The catalytic performance of these new water oxidation materials will be discussed.4

References

[1] (a) Duan, L.; Bozoglian, F.; Mandal, S.; Stewart, B.; Privalov, T.; Llobet, A.; Sun, L. Nature Chem. 2012, In press (b) Concepción, J. J.; Jurss, J. W.; Templeton, J. L.; Meyer, T.J. J. Am. Chem. Soc., 2008, 130 (49), 16462-16463.

[2] (a) Sala, X.; Rodríguez, M.; Romero, I.; Escriche, L.; Llobet, A. Angew. Chem. Int. Ed. 2009, 48, 2842. (b) Sala, X.; Cramer, C.J.; Gagliardi, L.; Llobet, A. et al. Angew. Chem. Int. Ed. 2010, 49(42), 7745-7747. (c) Francas, L.; Sala, X.; Escudero-Adan, E.; Benet-Buchholz, J.; Escriche, L.; Llobet, A. Inorg. Chem. 2011, 50(7), 2771-2781.

[3] (a) Li, L.; Duan, L.; Xu, Y.; Gorlov, M.; Hagfeldt, A.; Sun, L. Chem. Commun., 2010, 46, 7307-7309. (b) Francàs, L.; Sala, X.; Benet-Buchholz, J.; Escriche, L.; Llobet, A. ChemSusChem 2009, 2, 321-228. (c) Concepción, J. J.; Jurss, J. W.; Hoertz, P. G.; Meyer, T.J. Angew. Chem., Int. Ed. 2009, 48, 9473. [4] (a) Mola, J.; Mas-Marzà, E; Sala, X.; Romero, I.; Rodríguez, M.; Viñas, C.; Parella, T.; Llobet, A. Angew. Chem. Int. Ed. 2008, 47, 5830-5832.

REF: FP1‐2


Photoluminescence properties in novel molecular and dendrimeric boron containing systems. The key role of the carboranyl substituents.

Albert Ferrer-Ugalde,a Rosario Núñez,*a Francesc Teixidor,a Clara Viñas,a Arántzazu González-Campo,a Emilio José Juárez-Péreza

aInstitut de Ciència de Materials de Barcelona,(ICMAB-CSIC), Campus UAB, 08193, Bellaterra. Email: [email protected]

There is an increasing interest in the application of carborane clusters, such as ortho-carborane (C2B10H12), in diverse fields like catalysis, materials science or biomedicine, due to its thermal stability, electron-withdrawing character and its low toxicity in biological systems. Moreover, they are an ideal group for the preparation of building blocks, which are highly stable and versatile. Taking advantage of these features, carborane clusters have been included in different kind of platforms such as dendrimers, porphyrins and others to obtain boron-rich systems.1 The recent development of new photoluminescent systems that incorporates carborane clusters has become a very important area to explore. Likewise, in the last 5 years our research group has been interested in the development of new boron-rich systems, which contain neutral (closo) or anionic (nido) clusters and exhibit fluorescence in many solvents at room temperature.2 In these examples, the effect of the clusters in the final properties of the different systems have been studied.

In this work, new derivatives of o-carborane with a styrene moiety are introduced and their photoluminescence properties studied.3 These carborane derivatives with different substituents were designed to be molecular systems that exhibit photoluminescent properties. Furthermore, new dendrimeric systems have been synthesized, in order to obtain new boron-rich compounds containing several carborane clusters in their periphery. Deep studies about their photoluminescence properties have been carried out and the role of the carboranyl-substituent has revealed to be decisive in their behaviour.

[1] (a) González-Campo, A.; Viñas, C.; Teixidor, F.; Núñez, R.; Sillanpää, R.; Kivekäs, R. Macromolecules, 2007, 40, 5644. (b) González-Campo, A.; Juárez Pérez, E. J.; Viñas, C.; Boury, B.; Kivekäs, R.; Sillanpää, R.; Núñez, R. Macromolecules 2008, 41, 8458. [2] (a) Lerouge, F.; Viñas, C.; Teixidor, F.; Núñez, R.; Abreu, A.; Xochitiotzi, E.; Santillan, R.; Farfán,N. Dalton Trans. 2007, 1896.(b) Juárez-Pérez, E. J.; Viñas, C.; Teixidor, F.; Santillan, R.; Farfán, N.; Abreu, A.; Yépez, R.; Núñez, R. Macromolecules 2010, 43, 150.(c) Lerouge, F.; Ferrer-Ugalde, A.; Viñas, C.; Teixidor, F.; Abreu, A.; Xochitiotzi, E.; Farfán, N., Santillan, R.; Sillanpää, R. Núñez, R. Dalton Trans. 2011, 40, 7541. [3] (a) Ferrer-Ugalde, A.; Juárez Pérez, E. J.; Teixidor, F.; Viñas, C.; Sillanpää, R.; Pérez-Inestrosa, E.; Núñez, R. Chem. Eur. J., 2012, 18, 544. (b) Popescu, A. R.; Musteti, A. D.; Ferrer-Ugalde, A.; Viñas, C.; Núñez, R.; Teixidor, F. Chem. Eur. J., 2012, 18, 3174.

REF: FP1‐3


On the role of solvents in the performance of inkjet printed organic solar cells

Ignasi Burgués1,2,*, Mariano Campoy-Quiles1, Laia Francesch2, Marco Stella2, Paul D. Lacharmoise2

1 Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Bellaterra, Spain 2 Cetemmsa Technological Centre, Mataró, Spain

Email: [email protected]

Abstract Control over the nanomorphology of polymer:fullerene blends is one of the key steps to reach high performance organic solar cells (OSC). During the coating of the active layer, the solvents are not only a vehicle for the blend compounds but also play an active role in the drying kinetics and film formation and thus in the resulting degree of phase separation of the two materials, determining the final morphology of the layer. Since these effects depend on the choice of the coating technique, it is interesting to understand the basic principles of solvent-related phenomena in order to transfer this knowledge to any ink-based coating technique. In this context, inkjet printing appears to be a good choice because of its easy patterning, solvent saving and potential compatibility with roll-to-roll.

Here we focus on the OSC workhorse material system (P3HT:PCBM) and will show our recent studies concerning the interaction between ink formulation and morphology of inkjet printed films. Different processing parameters are also examined and their correlation with the morphology of the organic layer is discussed.

References [1] J.T. Davis, G.P. Spada, Chem. Soc. Rev., 2007, 36, 296-313. [1] E. Tekin, B. de Gans, U. S. Schubert, J. Mat. Chem. 2004, 14, 2627–2632. [2] Y. Yao, J. Hou, Z. Xu, G. Li, Y. Yang Adv. Funct. Mat. 2008, 18, 1783–1789. [3] B. Schmidt-Hansberg, H. Do, A. Colsmann, U. Lemmer, W. Schabel, Eur. Phys. Jour. Spec. Top. 2009, 166, 49–53. [4] C. N. Hoth, S. A. Choulis, P. Schilinsky, C. J. Brabec, Adv. Mat. 2007, 19, 3973-3978. [5] C. N. Hoth, P. Schilinsky, S. A. Choulis, C. J. Brabec, Nano Lett. 2009, 9, 2806-2813. [6] A. Lange, M. Wegener, C. Boeffel, B. Fischer, A. Wedel, D. Neher, Sol. Ener. Mat. Sol. Cell. 2010, 94, 1816-1821. [7] M. Campoy-Quiles, Y. Kanai, A. El-Basaty, H. Sakai, H. Murata, Org. Elec. 2009, 10, 1120–1132.

REF: FP1‐4


Figure 1. Schematic illustration of the formation of a CA-MOF made of

Synthesis of new nanoscale MOFs for contrast agent applications Arnau Carné1, Inhar Imaz1, Daniel Maspoch1,2

1CIN2 (ICN-CSIC), Institut Català de Nanotecnología, Campus UAB, Bellaterra, Spain. [email protected],

2Institució Catalana de Recerca i Estudis Avançats (ICREA), 08100 Barcelona, Spain.

Resulting from the combination of multitopic organic ligands with inorganic cores, Metal-Organic Frameworks (MOFs) have very recently been proposed for biomedical applications due to their interesting magnetic properties, extremely high surface areas (up to 10000 m2/g) providing better drug accommodation within the pores than other existing drug-delivery systems, versatile pore size, shape and functionality for post–synthetic grafting of drug molecules and tuning the MOF-drug interactions, and their possible miniaturization at the nanometer length scale. In this field, some advances have been done in the development of MOFs capable to act as contrast agents (CA) for Magnetic Resonance Imaging (MRI).1 In this communication, we will present a new synthetic strategy based on the use of metallo-macrocyclic contrast agents as bridging organic building blocks to connect metal ions along the space, thus forming novel MOFs that integrate their corresponding MRI diagnostic applications (hereafter called CA-MOFs). Following this approach, we will show the first synthesized CA-MOFs made of metal ions (e.g. Gd(III), Cu(II), etc.) and the macrocyclic ligand DOTP (Fig. 1). Significantly, these CA-MOFs have also been synthesized at the nanoscale in the form of nanowires of less than 100 nm in length and 10 nm in diameter. Finally, we will present their exceptional stabilities and dispersability in physiological media, their very low toxicity and promising CA properties, making them perfect candidates for their use in MRI.

References

[1]. Della Rocca, J.; Liu, D.; Lin, W. Acc. Chem. Res. 2011, 44, 957-968

REF: FP1‐5


Cyclobutane containing mixed peptides: folding and gelation properties

Sergi Celis, Ona Illa, Rosa M. Ortuño

Universitat Autònoma de Barcelona, Deparatament de Química, 08193-Cerdanyola del Vallès, Spain, [email protected]

Abstract Mixed peptides were previously synthesized combining 1,2-cyclobutane and alkyl linear amino acids, in this instance glycine, -alanine and GABA. High-NMR resolution studies and theoretical calculations were performed on tetrapeptides to conclude that -sheet or helical folding is adopted depending on the length of the alkyl chain.1

Gelation abilities of such compounds have been studied recently to afford many gels in a wide range of solvents for tetrapeptides and in polar protic solvents for a hexapeptide. Minimum gelation concentration has been determined for all them. Spectroscopic techniques and computational calculations have been used to investigate their supramolecular structure and some properties of the gels. Glycine tetrapeptide assembles into defined fibers while the rest of tetrapeptides give less defined structure organized in bundles. NMR experiments and theoretical calculations suggest a helical folding for glycine tetrapeptide and have allowed determining its transition temperature of sol-gel in deuterated toluene.

References [1] Celis, S.; Gorrea, E.; Nolis, P.; Illa O.; Ortuño, Rosa M. Org. Biomol. Chem. 2012,10, 861-868.

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MeO2Ca) b) c)

d)

Figure 1, a) Glycine tetrapeptide structure. b) Gly‐tetra gels at 7, 15 and 40 mM in toluene. c) SEM from gly‐tetra 40 mM xerogel. d) Computed hexadecameric aggregate of gly‐tetra showing helical folding.

REF: FP1‐6


FLASH PRESENTATIONS II


The application of cork in the removal of heavy metals from aqueous solutions

Enrique Ruperto Navarrete Hernández, Cristina Palet Ballús, Montserrat López Mesas Universidad Autónoma de Barcelona, Barcelona, Spain,

[email protected]

Abstract

In this work the ability of three different particle sizes of cork waste to remove Cd(II) and Pb(II) from aqueous solutions has been studied. Different parameters of the biosorption, biodesorption of metals and reuse of cork biomass were investigated. The maximun biosorption efficciency was found at pH 5 independently that if the metals were in an individual or mixed solution, showing a pH dependent profile. When a solution of the mixed metals was studied, the Cd(II) uptake decreased comparing with the individual metal solution, wich means a competition between the metals for the corresponding active groups of cork, which was also corroborated by P-factor modeling approach. This behavior probably is due to a lower attraction of Cd(II) to cork in front of Pb(II). Heavy metals recovery and biomass reusing are important keypoints for the financial competitivenes of biosorption systems over other processes. Furthermore, as an example, the biodesorption of heavy metals from cork was checked by using different kind of solutions (acid, with some complexing agents, etc). The best recovery efficient was found when HNO3 at strong pH was used. The research about the reuse of cork biomass revealed that it can be recyclable through several cycles of metals biosorption-biodesorption process. Recently, we have been explored with nanoparticles of Au and Ag immobilized on the cork surface. The purpose is to use this modified cork as an additional alternative option for the metal sorption purpose. In this sense, the immobilized Au and Ag nanoparticles change the surface functionality of cork, also increasing the surface area-volume ratio which can increase the sorption capacity and efficiency of this new material [1-3]. Finally, the cork has been evaluated by FTIR and SEM in order to determinate if the biosorption/biodesorption processes modify its chemical structure and morphology, and to check the presence of the nanoparticulated systems assayed. In conclusion, it can be said that cork has been proved to be an efficient biomaterial useful for the purpose removing heavy metals, without causing an alteration by the process [4]. References [1] Chen. Y, Wang. J, Preparation and characterization of magnetic chitosan nanoparticles and its application for Cu(II) removal, Chemical Engineering Journal, 2011, 168, 286-292. [2] Abdullah. A, Nabil. A, Saqr. M, Removal of Pb(II) and Cd(II) ions from water by Fe and Ag nanoparticles prepared using electro-exploding, Environ Sci Pollut Res, 2012, doi:10.1007/s11356-012-0788-1. [3] Yantasee. W, Warner. C.L, Sangvanich. T, Addleman. R.S, Carter. T.G, Warner. M.G, Removal of heavy metals from aqueous systems with thiol functionalized superparamagnetic nanoparticles, Enviromental Science and Technology, 2007, 41, 5114-5119. [4] Ariana. M.A, Catarina. I.A, Joana. C, Patricia. C, Susana. P, Victor. J.P, Cidália. M.S, Rui. A.R, Use of cork powder and granules for the adsorption of pollutants. Rev., 2012, 1-15.

REF: FP2‐1


Synthetic microengines for environmental and sensing purposes

Maria Guix1, Joseph Wang2 and Arben Mekoçi3

1 CIN2(ICN-CSIC), Catalan Institute of Nanotechnology, 08193 Bellaterra, Spain, [email protected] 2 Department of Nanoengineering, University of California-San Diego, 92093 La Jolla, California.

3 CIN2(ICN-CSIC), Catalan Institute of Nanotechnology, 08193 Bellaterra, Spain. Abstract Self-propelled synthetic microengines synthesized by template-based methods1 represents a mass production and low-cost approach compared to the strain engineering of nanomembranes on polymers.2 These tubular microengines base their autonomous movement on the the catalytic reaction held in the inner platinum surface in the presence of hydrogen peroxide. A bubble-induced propulsion mechanism takes place, which is combined with the magnetic guidance of the device thanks to a magnetic layer incorporated during the microengine fabrication. Such microengines can present a gold outer layer, which can be used to functionalize them with different receptors, using the surface chemistry of self-assembled monolayers (SAMs), to perform the detection or selective capture and isolation of certain analytes. The convenient modification of template based microengines with a lectin bioreceptor (Concanavalin A) permited the selective capture of E. coli, in addition to the uptake of polymeric drug-carrier particle providing an attractive motion-based theranostics strategy.3 Smaller size of template-based microengines enables us to follow easily the bacteria pick-up, as well as the discrimination against nontarget cells, by using standard optical microscopy. Alternative applications focused on environmental purposes had been developed, demostrating the transport and removal of oil droplets. Microtubular engines had been modified with a superhydrophobic able to adsorb oil by means of its strong adhesion to a long chain of self-assembled monolayers (SAMs) of alkanethiols created on the rough gold outer surface of the device. The interaction of the resultant SAM-coated Au/Ni/PEDOT/Pt microengine is demostrated by the capacity of loading and transporting multiple small oil droplets. The influence of the alkanethiol chain length, polarity, and head functional group had been examined related to the surface hydrophobicity of the microengine. The integration of oil-sorption properties into self-propelled microengines holds great promise for the remediation of oil-contaminated water samples and for the isolation of other hydrophobic targets, such as drugs.4 References [1] W. Gao, S. Sattayasamitsathit, J. Orozco and Joseph Wang. J. Am. Chem. Soc., 2011,133, 11862–11864. [2] A. A. Solovev, Y. F. Mei, E. B. Urena, G. S. Huang, O. G. Schmidt. Small 2009, 5, 1688–1692. [3] S. Campuzano, J. Orozco, D. Kagan, M. Guix, W. Gao, S. Sattayasamitsathit, J. C. Claussen, A. Merkoçi, J. Wang. Nano Lett. 2012,12, 396–401. [4] M. Guix, J. Orozco, M. García, W. Gao, S. Sattayasamitsathit, A. Merkoçi, A. Escarpa, J. Wang. ACS Nano, 2012, DOI: 10.1021/nn301175b.

REF: FP2‐2


New bioconjugated rhenium and technetium carbonyls by transmetallation reaction with zinc derivatives

J. Lecina1*, A. Carrer2, A. Álvarez-Larena3, U. Mazzi2, L. Melendez-Alafort4 and J. Suades1

1Departament de Química, Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain, [email protected]

2Dept of Pharmaceutical Sciences, University of Padova, Italy

3X-ray Diffraction Service, Universitat Autònoma de Barcelona, Spain

4Istituto Oncologico Veneto IRCCS, Padova, Italy Abstract We developed an innovative method to prepare new rhenium and technetium compounds for radiopharmaceutical application by means of a transmetallation reaction with Zn (II) complexes.[1] The studied zinc compounds were prepared from the succinimidyl ester of isonipecotic acid (1) which acts as a synthon and allows to synthesized bioconjugated compounds through a peptide coupling reaction.

Using the transmetallation reaction (following scheme), we prepared new techentium-99m bioconjugated compounds which were characterized by radio-HPLC analysis. They showed a similar retention time in relation to the cold homologous rhenium complexes.

It should be emphasized that this reaction is so favourable that takes place in water although the solubility of the Zn (II) dithiocarbamates are extremely low. Consequently, the low solubility of unlabeled biomolecules in the reaction medium allows to obtain Tc-99m products with high specific activity. This approach would be a good method to prepare radiopharmaceutical. References [1] J. Suades, J. Lecina, A. Carrer, U. Mazzi, Patent pending to Universitat Autònoma de Barcelona.

REF: FP2‐3


Study of Kinetics and Mechanisms of Liquid Phase Photocatalytic Reactions with Titanium Dioxide (TiO2)

Juan Felipe Montoya, José Peral and Pedro Salvador

Departament de Química, Universitat Autònoma de Barcelona, Cerdanyola del Vallès (08193), Spain

e-mail: [email protected]

Abstract Titanium Dioxide (TiO2) has attracted the attention of many researches in the last 25 years. This semiconductor has been applied for solar energy conversion, tiles and glasses with superhydrophilic surface properties, and photooxidation of organic pollutants in gaseous and liquid phase [1]. In spite of this interest, detailed mechanisms of primary events involved in the photocatalytic oxidation of organic molecules in liquid phase TiO2 dispersions, are far to be clear. It is a common practice in the field of photocatalysis the use of the Langmuir Hinshewoold (LH) kinetic model to analyze experimental results of organics photooxidation. However, in the last few years several research groups have made objections to the suitability of this kinectic model for a complete understanding of photocatalytic reactions [2,3]. Recently, it has been proposed an alternative kinetic model known as the Direct Indirect (DI) model [4]. In this work we show experimental evidence to validate the two main hypotheses of the DI model: on one hand, a kinetic study of photooxidation of formic acid, phenol and benzene in different solvents demonstrate that the rate of photooxidation and its dependence with photon flow depends to a high degree on the electronic interaction between the substrate and the TiO2 surface . On the other hand, the study of liquid phase photocatalytic oxidation of acetonitrile and benzene in the absence of water and dissolved molecular oxygen allow us to propose an alternative mechanism for photooxidation of organic molecules invoking the participation of TiO2 surface bridging oxygen ions (>Obr

2-), bridging oxygen radicals (-Obr-) and bridging oxygen vacancies (V[>Obr

2-]) as reaction intermediates and disregard the classical role assigned to OH. radicals as main oxidizing species in liquid phase photocatalytic reactions.

References [1] A. Fujishima, X. Zhang, D. A. Tryk, Surf. Sci. Rep., 2008, 63, 515-582 [2] A. V. Emeline, V. K. Ryabchuk, N. Serpone, J. Phys. Chem. B, 2005, 109, 18515-18521. [3] D. F. Ollis, J. Phys. Chem. B, 2005, 109, 2439-2444 [4] D. Monllor-Satoca, R. Gomez, M. Gonzalez-Hidalgo, P. Salvador, Catalysis Today, 2007, 129, 247-255.

REF: FP2‐4


Diversity Oriented and Enantioselective Synthesis of Gabosines and Anhydrogabosines

Miguel Ángel Fresneda, Marta Figueredo, Pau Bayón

Departament de Química, Universitat Autònoma de Barcelona, Campus de Bellaterra 08193, Cerdanyola del

Vallès, Spain e-mail: [email protected]

Abstract The gabosine family comprises a group of secondary metabolites isolated from various Streptomyces strains that present a polyhydroxylated methyl cyclohexane system as the common constitutional feature.1 Some other compounds isolated from natural sources display also a structural pattern within the gabosine family. There are also several known epoxyquinone natural products with anhydrogabosine structure (Figure 1).

Figure 1: Some members of the gabosine and anhydrogabosine families.

In our laboratories, we have developed a flexible, diversity oriented methodology for the synthesis of these natural products, starting from a common material. In the last years, we have been working in the methyl substituted gabosines and completed the stereoselective synthesis of gabosines N, O, A, B and F, and the anhydrograbosines epoformin and epiepoformin.2 As for my thesis, I have been carrying out studies focused on the hydroxymethylated derivatives and completed the preparation of gabosines C and F,3 as well as some advanced intermediates in the synthesis of gabosines E, D and the anhydrogabosines epoxydon, epiepoxydon and phyllostine.

References [1] (a) Bach, G.; Breiding-Mack, S.; Grabley, S.; Hammann, P.; Huetter, K.; Thiericke, R.; Uhr, H.; Wink, J.; Zeeck, A. Liebigs Ann. Chem. 1993, 241-250. (b) Tang, Y.-Q.; Maul, C.; Hofs, R.; Sattler, I.; Grabley, S.; Feng, X.-Z.; Zeeck, A.; Thiericke, R. Eur. J. Org. Chem. 2000, 149-153. [2] (a) Alibés, R.; Bayón, P.; de March, P.; Figueredo, M.; Font, J.; Marjanet, G. Org. Lett. 2006, 8, 1617-1620. (b) Toribio, G.; Marjanet, G.; Alibés, R.; de March, P.; Font, J.; Bayón, P.; Figueredo, M. Eur. J. Org. Chem. 2011, 1534-1543. [3] Fresneda, M. A.; Alibés, R.; Font, J.; Bayón, P.; Figueredo, M. J. Org. Chem. 2012, xxxx-xxxx.

REF: FP2‐5


Development of electronic tongue for simultaneous determination of heavy metals in soil samples and monitoring of biosorption processes.

Deivy Wilson Massó, Salvador Alegret, Manel del Valle, Antonio Florido1

Sensors and Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia, Spain, [email protected]

1 Departament d’Enginyeria Química, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain

Abstract

This paper addresses the development, optimization and application of electronic tongue (ET) analysis system for determination of heavy metals. In advance to electronic tongue building, two novel PVC membrane ion selective electrodes for Pb(II), are reported [1]. The first application of the proposed ET was the determination of lead (II), cadmium (II), copper (II) and zinc (II) in soil samples. This ET consisted of 9 ISEs of polymeric membrane previously characterized in their response: Nernstian behaviour, concentration range of approximately 10-6 to 10-2 M and selectivity coefficients confirming that all sensors had cross response for the target ions. The mixed response of the sensor array was modelled employing Artificial Neural Networks. The real samples application was satisfactory, the obtained results were compared and validated against flame atomic absorption spectroscopy reference methodology, with correlations of the comparison R2>0.948 for the four heavy metals considered. The other application of the proposed methodology was the monitoring of biosorption processes of heavy metals on grape stalk wastes (used as biosorbent). The real-time sorption monitoring of Cu2+

[2], binary mixture of Cu2+, Zn2+ and Cu2+, Pb2+, ternary mixture of Cu2+, Zn2+, Pb2+ and Cu2+, Zn, Cd2+ and in all cases the cation exchanged and released (Ca2+) in the effluent solution were performed by potentiometric sensors (with tubular configuration) by combining flow-injection techniques (FIP) and electronic tongue (ET) detection. The result of the monitoring process was successful and spectroscopic techniques were employed in order to validate the results obtained with the reported methodology. The sorption performances of grape stalks were also evaluated by means of well-established sorption models.

References

[1] D. Wilson, M. Arada, S. Alegret, M. del Valle, J. Hazard. Mater., 2010, 181, 140-146. [2] D. Wilson, M. del Valle, S. Alegret, C. Valderrama, A. Florido, Talanta, 2012, 93, 285- 292. l. Chem. 2012,10, 861-868.

REF: FP2‐6


FLASH PRESENTATIONS III


Scheme 1. Influence of B-halogen vertexes on the redox potential E1/2(CoIII/CoII) vs Fc+/Fc

Stepwise sequential redox potential modulation possible on a single platform

Marius Lupu1, Francesc Teixidor, Ariadna Pepiol, Reijo Sillanpää, Clara Viñas

1Institut de Ciència de Materials de Barcelona (CSIC),Campus UAB,08193 Bellaterra (Spain) [email protected]

Abstract Electron transfer is fundamental in many processes of life, including oxygen binding, photosynthesis

and respiration.[1] All organisms obtain energy by transferring electrons from an electron donor to an electron acceptor.[2] Following our research,[3] in this work we show a first case of an artificial large downhill sequence with well defined, characterized, and structurally similar, individual electron donors and acceptors made from a common frame. The cluster, [3,3’-Co(1,2-C2B9H11)2]

- ([1]-) has been proven to be an excellent platform to produce a stepwise tunable redox potential

system by dehydroiodination. We have shown (Scheme 1) that each new B-I bond in [1]- produces a shift of +0.133V.[4] With the same platform [1]- and with the addition up to 8 iodine atoms, there has been a drop of E1/2 (CoIII/CoII) from -1.80V in [1]- to -0.68V in I8[1]- (vs Fc+/Fc). A practical application of this tunability has been observed in the growth of Polypyrrole. A dramatic modification of the growth curve has been experienced. The predictability and accessibility of such E1/2 tunable platform may lead to numerous possibilities, mainly in nanoscience and molecular materials.

References [1] R.E. Blankenship in Molecular Mechanisms of Photosynthesis, Blackwell Science, Oxford, 2002, chap. 6-7. [2] a) A. Amunts, O. Drory, N. Nelson, Nature 2007, 447, 58-63; b) M. R. Wasielewski, J. Org. Chem. 2006, 71, 5051-5066; c) R. Lomoth, A. Magnuson, M. Sjödin, P. Huang, S. Styring, L. Hamarström, Photosynth. Res. 2006, 87, 25-40; d) J. H. Alstrum-Acevedo, M. K. Brennaman, T. J. Meyer, Inorg. Chem. 2005, 44, 6802-6827. [3] P. Gonzalez-Cardoso, A. I. Stoica, P. Farràs, A. Pepiol, C. Viñas, F. Teixidor, Chem. Eur. J. 2010, 16, 6660-6665. [4] A. Pepiol, F. Teixidor, R. Sillanpää, M. Lupu, C. Viñas, Angew. Chem. Int. Ed. 2011, 50, 12491–12495.

REF: FP3‐1


Computational Analysis on the Mechanism of Homogeneous Gold-catalyzed Reactions

Sergi Montserrat1, Gregori Ujaque1, Agustí Lledós1

1Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Espanya [email protected]

Abstract

The homogeneous gold-catalyzed transformation of unsatured precursors is a very active research topic in the field of catalysis. Some of the main advantages of these reactions are the high atom economy and the exceptionally mild reaction conditions, which combined with the gain in molecular complexity, leads to a growing number of applications in total synthesis. Despite the fact that new reactions and methodologies are continuously developed, the complete understanding of how these processes take place, is generally missed. In several cases only hypothetical mechanisms have been proposed, which can be partially attributed to the high reaction rates. At this point, theoretical techniques play an important role as they provide valuable information at the molecular level, which combined with experimental evidences, leads to a better understanding of the reaction mechanism. This is the aim of this thesis performed in closed collaboration with experimental groups. Particularly, we have studied the intramolecular cycloaddition of allenedienes catalyzed by gold and platinum complexes. The mechanism for the [4C+3C] cycloaddition has been elucidated.[1] Moreover the chemioselectivity between (4+3) and (4+2) products has been related with the effect of the number of allene substituents and the chemical properties of the catalyst.[2-4] The mechanism of the intermolecular version of the cycloaddition of allenedienes is currently being investigated. The gold(I)-catalyzed intermolecular oxyarylation of alkynes has been also analyzed. The results obtained on this thesis suggest that the unexpected regiochemistry can be explained by means of a concerted [3,3’] sigmatropic rearrangement.[5] The intramolecular version of this reaction has been also studied; more specifically we have been interested on the effect of the gold ligands, and whether a carbene intermediate is involved or not in the mechanism.

References [1]B. Trillo, F. López, S. Montserrat, G. Ujaque, L. Castedo, A. Lledós and J. L. Mascareñas, Chem. Eur. J., 2009, 15, 3336. [2]I. Alonso, B. Trillo, F. López, S. Montserrat, G. Ujaque, L. Castedo, A. Lledós and J. L. Mascareñas, J. Am. Chem. Soc., 2009, 131, 13020. [3]S. Montserrat, I. Alonso, F. López, J. L. Mascareñas, A. Lledós, G. Ujaque, Dalton. Trans., 2011, 40, 11095. [4]S. Montserrat, G Ujaque, F. López, J. L. Mascareñas, A. Lledós, Top. Curr. Chem, 2011, 302, 225. [5]A. B. Cuenca, S. Montserrat, K. M. Hossain, G. Mancha, A. Lledós, M. Medio-Simón, G. Ujaque and G. Asensio, Org. Lett., 2009, 11, 4906.

REF: FP3‐2


Molecular modeling role in the design of new artificial metalloenzymes

Victor Muñoz Robles, Jean-Didier Maréchal, Agustí Lledós

Departament de Química, Universitat Autònoma de Barcelona Edifici C.n., 08193 Cerdonyola del Vallés, Barcelona (Spain).

Abstract Nature has always been a model for catalysis in many different aspects. Enzymes are able to catalyze complex reactions and have very interesting features such as thermostability and enantiospecificity. Trying to mimetize those molecular entities, the idea of creating artificial metalloenzymes was born. This new species are expected to represent alternatives in organic and fine chemistry by carrying on reactions otherwise hardly performed on a chemical bench. The success of the design of those artificial enzymes highly relies on the understanding of the molecular events that occur during the recognition process between the biological scaffold and the metallic cofactor. Molecular modeling approach could elucidate key molecular information for such purpose. However several limitations must be overcome for the design of artificial metalloenzymes.

In this context our group has developed an integrative protocol approach to deal with metal – containing cofactors and aid in the design of artificial metalloenzymes. The designed protocol has been applied on different systems in order to give key catalytic and structural information. The first study was done on an abzyme designed against different porphirinic cofactors1. This molecule was able to perform an oxidative reaction, however due to a bad resolution x-ray structure few structural information was available. With our docking protocol we manage to refine the original structure and fully localize the metallic cofactor. On another work we obtained fundamental information about the catalytic mechanism of an imine ATH reaction performed by an artificial iridium based metalloenzyme2. This information will be used to further optimize the molecular entity.

References [1] de Lauzon, S., Mansuy, D. and Mahy, J.-P. European Journal of Biochemistry 2002, 269: 470–480. [2] M Dürrenberger, Marc Heinisch, Tillmann Wilson, Yvonne M Rossel, Thibaud Nogueira, Elisa Knörr, Livia Mutschler, Annette Kersten, Karoline Zimbron, Malcolm Jeremy Pierron, Julien Schirmer, Tilman Ward, Thomas R. Angewandte Chemie International Edition 50, 123: 3082 - 3085.

REF: FP3‐3


Palladium Nanoparticles in catalysis: Tapping into the Potential of Tris-Imidazolium Salts for Nanoparticle Stabilization

Marc Planellas, Alexandr Shafir, Roser Pleixats

Department of Chemistry. Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193-Barcelona, Spain. [email protected]

Abstract Metal nanoparticles are attractive catalysts due to their large surface-to-volume ratio that provides a larger number of active sites per unit area.1 Inspired by the proclivity of various palladium sources to form nanoparticles in imidazolium-based ionic liquids, we found that tris-imidazolium salts2, developed in our group, bearing hexadecyl chains and a bridging mesitylene moiety are potent stabilizers of palladium nanoparticles. The materials was efficiently prepared via hydrogenation of Pd(dba)2 (in the presence of stabilizer). The palladium nanoparticles have been isolated in pure form and proved effective in C-C coupling reactions3 and hydrosilylation of internal alkynes.4 The materials spectral and catalytic properties varied as a function of the counterions; this differentiation was attributed to the presence, in some cases, of surface-bound N-heterocyclic carbenes (solid state 13C CP MAS NMR).

References [1] (a) Roucoux, A.; Schulz, J.; Patin, H. Chem. Rev. 2002, 102, 3757-3778. (b) Moreno-Mañas, M.; Pleixats, R. Acc. Chem. Res. 2003, 36, 638–643. (c) Nanoparticles and Catalysis. Astruc, D., Ed.; Wiley-VCH: Weinheim, 2008. [2] M. Trilla, R. Pleixats, T. Parella, C. Blanc, P. Dieudonné, Y. Guari, M. Wong Chi Man, Langmuir 2008, 24, 259–265. [3] Planellas, M.; Shafir, A.; Pleixats, R., Adv. Synth. Catal., 2012, 354, 651-662. [4] In preparation

REF: FP3‐4


New derivatives of 1,1’-binaphthalene in the field of chiral recognition: enantiodifferentiation and enantioselective synthesis

Josep Recasens, Albert Virgili and Pedro de March Universitat Autònoma de Barcelona, Bellaterra, Spain, [email protected]

Abstract The main research topic in our group is based on the synthesis of new enantiopure compounds and their application as chiral solvating agents (CSAs) and as chiral auxiliaries [1]. With this purpose, we have decided to synthesize new binaphthalene derivative compounds conveniently functionalized at 2 and 2’ positions. These compounds present the characteristic of having a stereogenic axis besides the chiral centers of the side chains. The preparation of five stereoisomers of 1,1’-(1,1’-binaphthalene-2,2’-diyl)bis(2,2,2-trifluoroethanol), 1, has been accomplished, and the absolute configuration of all of them has been determined by X-ray diffraction and CHPLC. The use of these new chiral auxiliaries in Diels-Alder reactions (reaction previously studied in our group [2]) is being studied using the new compounds 2 and 3 as dienophiles. Moreover, the intramolecular [2+2] photocycloaddition reaction using the acrylic ester 4 and the crotonyl ester 5 will be studied.

References

[1] M. Pomares, F. Sánchez-Ferrando, A. Virgili, A. Alvarez-Larena, J.F. Piniella, J. Org. Chem., 2002, 67, 753-758. [2] P. Nolis, A. Virgili, J. Org. Chem., 2006, 71, 3267-3269.

REF: FP3‐5


Influential Role of Ethereal Solvent on Organolithium Compounds: the Case of Carboranyllithium

Ana Daniela Musteti, Adrian-Radu Popescu, Albert Ferrer-Ugalde,

Clara Viñas, Rosario Nuñez, and Francesc Teixidor

Institut de Ciència de Materials de Barcelona(CSIC),Campus UAB,08193 Bellaterra (Spain)

[email protected]

Abstract

The influence of ethereal solvents (diethyl ether, tetrahydrofuran or dimethoxyethane) on the formation of organolithiated compounds has been studied on the 1,2-C2B10H12 platform. This is very attractive because it contains two Cc-H adjacent units ready to be lithiated. Carboranes have raised interest in fields as diverse as catalysis, materials science, supramolecular chemistry, and medicine, among others,[1] therefore the synthesis of monosubstituted derivatives of o-carborane in good yields and in as much pure form as possible is very relevant. The first reason is the atom economy,[2]

and secondly, but not less important, because the cluster keeps a second position, a Ccluster-H (Cc-H), for further reaction with a different electrophile. The formation of carboranyl disubstituted species has been attributed to the existence of an equilibrium in which the carboranyl monolithiated species disproportionates into dilithium carborane and pristine carborane. In this work we have done further research to understand the role of the Li+ in C-X (X=C, S or P) coupling reactions. To do so we have used the equilibrium shown in Scheme 1 and studied: 1) the way Li+ binds to Cc in the carboranyl fragment and how the solvent influences in such a binding to drive the reaction to the generation of mono- and disubstituted carboranes, 2) to determine if the equilibrium shown in Scheme 1 is decisive for the high-yield preparation of monosubstituted 1-R-1,2-C2B10H11, or if there are other factors to be taken into account, and 3) to learn why such an uncommon equilibrium takes place.

References [1] a) J. Plesek, Chem. Rev. 1992, 92, 269 –278; b) M. F. Hawthorne, A. Maderna, Chem. Rev. 1999, 99, 3421 – 3434; c) J. F. Valliant, K. J. Guenther, S. Arienne, S. King, P. Morel, P. Schaffer, O. O. Sogbein, K. A. Stephenson, Coord. Chem. Rev. 2002, 232, 173 – 230; d) F. Teixidor, C. Viñas, A. Demonceau, R. Nuñez, Pure Appl. Chem. 2003, 75, 1305; e) I. T. Chizhevsky, Coord. Chem. Rev. 2007, 251, 1590 –1619; f) L. Deng, Z. W. Xie, Coord. Chem. Rev. 2007, 251, 2452 – 2476; g) I. B. Sivaev, V. I. Bregadze, Eur. J. Inorg. Chem. 2009, 1433 –1450; h) Carboranes 2nd ed. (Ed.: R. N. Grimes) Academic Press (Elsevier), London, 2011; i) Boron Science: New Technologies and Applications (Ed.: N. S. Hosmane), CRC, Boca Raton, FL, 2011. [2] a) P. A. Wender, B. L. Miller, Nature 2009, 460, 197 – 201; b) T. Newhouse, P. S. Baran, R. W. Hoffmann, Chem. Soc. Rev. 2009, 38, 3010 – 3021.

REF: FP3‐6


FLASH PRESENTATIONS IV


Preparation of micro and nanoparticulate materials using microemulsions with CO2-expanded solvents.

P.E. Rojas1,2, Mary Cano-Sarabia 1,2, Santi Sala 2,1, Jaume Veciana1,2*, Nora Ventosa1,2*

1 Department of Molecular Nanoscience and Organic Materials, Institut de Ciencia de Materials de Barcelona (CSIC), Bellaterra, 08193 Barcelona, Spain

2 CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193 Barcelona, Spain

Abstract It has been estimated that 40% or more of newly developed pharmaceutically active substances will be poorly water soluble. The dissolution rate may be enhanced by forming particles with high surface area [1]. The use of microemulsions as nanotemplates is one of the versatile preparation technique which enables control of particle structural characteristics such as size, geometry, morphology, homogeneity and surface area. Microemulsions are isotropic, macroscopically homogeneous, optically transparent and thermodynamically stable liquid phases containing at least three components [2].Their thermodynamic stability and their nanostructure are two important characteristics that distinguish them from ordinary emulsions. The main problem when using conventional microemulsions for nanoparticles synthesis is the separation and removal of solvent from products. Compressed fluids (CF) used as solvents offer several advantages such as fast reaction speed, rapid separation and easy removal of solvent from nanoparticles. Another advantage of using CFs is that microemulsions can be formed and destroyed by pressure changes. Recently in my group (Nanomol of ICMAB-CSIC) it has been observed that some ternary systems composed of “water/ organic solvent/compressed CO2” at certain conditions can form oil-in-water microemulsions (o/w) where the water is the continuous phase and the dispersed phase are nanodomains of CO2-expanded organic solvent (Figure 1)[3]. A comprehensive study of these systems and their use as templates for crystal growth of organic nanoparticles are the main objective of my PhD thesis. The phase behaviour of the ternary system was carried out. I study the formation and destruction of microemulsion by visual inspection using a high pressure variable volume view cell and by spectroscopic techniques thanks to a UV-vis spectrophotometer coupled online with a high pressure spectroscopic cell connected to the high pressure phase analyser. Another proof of the existence of these microemulsions is the ability of dissolving a water insoluble compound in the “CO2-expanded organic solvent” nanodomains.

CO2

Water

OrganicSolvent

PMicroemulsion Solution

Figure 1: Reversible transformation through pressure changes from a microemulsion μ(L2@L1) to a

solution.

References

1. B. E. Rabinow, Nature Reviews, 3 (2004) 785

2. C.Stubenrauch, Microemulsions: Background, new concepts, applications, perspectives.Wiley, 2009

3. N. Ventosa, J. Veciana, S. Sala, M. Cano, (2008) Patent priority number: P200803753

REF: FP4‐1


Metallothioneins as detoxifying agents for pb(ii)

C. Pérez-Zúñiga, 1 Ò. Palacios, 1 S. Atrian, 2 M. Capdevila1

1Dept. Química, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain); [email protected]

2Dept. Genètica, Universitat de Barcelona, E-08028 Barcelona (Spain)

Abstract Lead is one of the major hazards in human health due to its wide distribution in the environment. Pb(II) preferentially interacts with proteins containing Zn(II) (ALAD, CadC, GATA, Zn-fingers) and Ca(II) (CaM, PKC, syt) causing not only interferences in some metabolic processes, mainly the biosynthesis of hemoglobin, but also the inhibition of several enzymes and damages to the central nervous system (CNS). Against these deleterious effects, living organisms have developed defense and Pb(II)-detoxification mechanisms among which we can find metallothioneins (MTs). Metallothioneins (MTs) are the most versatile metal-binding proteins present in all organisms because their unusually high Cys content confers them a high capacity to chelate heavy metal ions, both in vivo and in vitro, allowing them to act as detoxifying agents. This work is focused in the determination of the capability of the four mammalian MT isoforms -MT1 and MT2 (both ubiquitous), MT3 (in CNS) and MT4 (in stratified epithelium) - to detoxify Pb(II) under physiological conditions (pH 7 and 37ºC), by means of spectroscopic (CD and UV-vis) and spectrometric (ESI-MS) techniques. The results obtained confirm that the Zn-loaded mammalian MTs isoforms show a quite differentiated behavior when binding Pb(II). Strikingly, Zn-MT4 is unable to bind Pb(II) while Zn-MT1, Zn-MT2 and Zn-MT3 can bind up to 10 Pb(II) equivalents quite readily. In spite of this capacity of MT1, MT2 and MT3 for forming Pb(II)-complexes, ESI-MS monitorization of the distinct Zn-MTx + Pb(II) reactions have shown that the distinct Zn- vs. Cu-thionein character of each isoform [1] clearly determine its capacity of retaining the initially bound Pb(II). Interestingly, among all mammalian MT isoforms, MT3 exhibited the best abilities to detoxify Pb(II). This final finding is especially relevant if taken into account that this isoform is only present in CNS and the damages that lead can precisely exert to its crucial structures. References [1] Ò. Palacios, S. Atrian, M. Capdevila J. Biol. Inorg. Chem., 2011 (DOI: 10.1007/s00775-011-0827-2)

Acknowledgements Financial support from the MICINN (Projects BIO2009-12513-C02-01 and -02) is acknowledged.

REF: FP4‐2


Synthesis and characterization of Goethite nanorods. TEM study of the phase change from Goethite to Hematite.

Leonardo Pérez-Mirabet1*, Eduardo Solano1 C. Frandsen2, T. Kasama3, Ramón Yáñez1, Josep Ros1

1Departament de Química, Universitat Autònoma de Barcelona 2 Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark

3 Center for Electron Nanoscopy, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark

*[email protected]

Abstract Goethite FeO(OH) nanorods have been obtained via hydrothermal synthesis in an improved from literature[1] ‘one-step’ procedure, for further applications in materials science. The resulting nanoparticles have been studied by different characterization techniques, including Mössbauer spectroscopy, Transmission Electron Microscopy (TEM) bright field images and electron holography. During the TEM characterization process, a change in the solid phase of the nanoparticles has been observed and studied in depth by taking and analyzing TEM images not only from the original and final different iron phases but also from the intermediate phase products. As the resulting obtained data show, the Goethite nanoparticles turn into Hematite Fe2O3 by the effect of the TEM electron beam. During the change process, some degradation degradation of nanoparticles have been observed.

References [1] Q. Dong, et al., J. Ceram. Soc. Jpn., 2009, 8, 881-886.

REF: FP4‐3


R2

NO2N

NN

NO N

R1R1

R1

R1

H

O

O

R2

NO2N

NN

NO N

R1R1

R1

R1

O

O

R1 = ciclohexyl, isopropylR2 = NO2, CF3

ZW MC

Fluorescence Non-Fluorescence

Base or Reduction

Acid or Oxidation

Fluorescent molecular switches: an electrochemical approach

Iluminada Gallardo, Gonzalo Guirado, Jordi Hernando and Gemma Prats

Departament de Química, Universitat Autònoma de Barcelona, 08193-Bellaterra (Barcelona), Spain

[email protected]

Abstract

In recent years, fluorescent molecular switches have been proposed as candidates for preparing nanosensors and molecular memories1 since one of the easiest ways to evaluate the role of these devices at nanoscale is by using fluorescence detection.2 Particularly interesting would be the design of molecular switches that could be triggered upon either a chemical or an electrochemical stimulus. The current presentation is devoted to show the synthesis, the chemical and electrochemical proprieties as well as the reversible interconversion mechanism between a the fluorescent zwitterionic form (ZW, ON) and the non-fluorescent Mesenheimer form (MC, OFF)3, a new family of molecular switches (Scheme 1). Some of the potential applications of this family are as high sensitivity chemical sensors, as optical materials for data storage as well as as fluorescent markers in biomedical applications.

References

[1] Molecular Switches (Ed.: B. Feringa), Wiley-VCH, Weinheim, 2002. [2] (a) M. Irie, T. Fukaminato, T. Sasaki, N. Tamai, T. Kawai, Nature 2002, 355, 335; (b) L. Zang, R. Liu, M. W. Holman, K.T. Nguyen, D.M. Adams, J. Am. Chem. Soc. 2002, 124, 10640- 10641. [3] R.O. Al-Kaysi, J.L. Bourdelande, I. Gallardo, G. Guirado, J. Hernando, Chem. Eur. J., 2007, 13, 7066-7074.

Scheme 1. Scheme of interconversion between the states “ON” and “OFF” of these fluorescent molecular switches.

REF: FP4‐4


Synthesis of new binaphthalenic C2-symmetry molecules with stereogenic axis and centers

Marta Sangüesa, Pedro de March and Albert Virgili

Universitat Autònoma de Barcelona, Bellaterra, Spain, [email protected]

Abstract The main research topic in our group is based on the synthesis of new enantiopure compounds and their application as chiral solvating agents (CSAs) and as chiral auxiliaries [1]. Our target is to introduce structural modifications in order to enhance the enantiomeric recognition obtained with the already known CSAs and therefore to improve the enantiomeric excess determination by Nuclear Magnetic Resonance (NMR). We have focused our research on the synthesis of new compounds with a common binaphthalenic structure. This moiety is very interesting since it introduces a stereogenic axis on these products, in addition to other chiral centers that might be present in the molecule. The presence of a C2-axial symmetry is very important in these applications because it simplifies the NMR spectra and it reduces the number of possible transition states. Starting from 2,2’-dibromo-1,1’-binaphthalene, 1, in its racemic form, the racemic diacid 2 has been obtained [2], which is the precursor for the synthesis of a set of ketones 3. The different reactivity of these ketones in reduction reactions has been studied, using both achiral metal hydrides as well as various methods of enantioselective reduction. Thus, various stereoisomers of diols 4 have been synthesized in enantiopure form, with very high enantiomeric excesses. Moreover, the absolute configuration of the synthesized diols 4 has been determined by resolution of the diacid 2, X-ray diffraction and CHPLC. Enantiopure diols 4 are interesting compounds in the field of chiral solvating agents and chiral auxiliaries. The use of them as CSAs is currently under study.

References [1] M. Pomares, F. Sánchez-Ferrando, A. Virgili, A. Alvarez-Larena, J. F. Piniella, J. Org. Chem., 2002, 67, 753-758. [2] S. Ôi, Y. Matsuzaka, J. Yamashita, S. Miyano, Bull. Chem. Soc. Jpn., 1989, 62, 956-957.

REF: FP4‐5


Photochromic nanocomposites as photoprotective coatings

Nuria-Alexandra Vázquez-Mera1,2, Claudio Roscini1, Jordi Hernando1, Daniel Ruiz-Molina2 1Departament de Química, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Spain,

2 Centro de Investigación en Nanociencia y Nanotecnología (CIN2-CSIC), Cerdanyola del Vallès, Spain, [email protected]

Abstract Owing to their capability to undergo reversible color changes upon irradiation with light, photochromic compounds have been proposed for a number of applications in optics, electronics, computing and materials science[1]. Among them, their use in photoprotective coatings of ophthalmic lenses to control eyes exposure to sunlight is currently the major commercial application, which requires the photochromic compounds to (i) display light-induced conversion from a transparent to a colored state, (ii) revert back thermally to the initial situation in absence of illumination and (iii) present fast color darkening and fading kinetics[2]. To date a number of organic photochromes have been developed to fulfill these requirements; however, achieving high switching speeds in solid materials for practical applications still remains a challenge[3]. This is due to the effect of the supporting matrix where these compounds are loaded, which induces dye aggregation due to poor miscibility and restricts the significant molecular motions typically involved in the interconversion between the two states of the photochromes. As a result, the thermal back-reaction rate of these compounds is largely slowed down with respect to solution, thus affecting the performance or even preventing the application of the final photochromic materials. In an attempt to overcome this limitation, in this work we have investigated: (1) the effect of photochrome concentration on the thermal back-reaction kinetics when dyes are directly dispersed within a number of different polymer films; and (2) a novel methodology to optimize the performance of such materials, which consists in the encapsulation of the photochromes into solid nanoparticles prior to their final incorporation within the supporting rigid matrices.

References [1] a) H. Dürr, H. Bouas-Laurent, Photochromism: Molecules and Systems, 1st ed., Elsevier,

Amsterdam 2003. [2] S. N. Corns, S. M. Partington, A. D. Towns, Color. Technol. 2009, 125, 249. [3] R. A. Evans, T. L. Hanley, M. A. Skidmore, T. P. Davis, G. K. Such, L. H. Yee, G. E. Ball, D. A.

Lewis, Nature Mater. 2005, 4, 249.

REF: FP4‐6


FLASH PRESENTATIONS V


Sulfonated Phosphines with Strong Electrowithdrawing Substituents for Biphasic Hydroformylation of Polar Alkenes

Daniel Peral, J. Carles Bayón

Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Spain, [email protected]

Abstract The biphasic aqueous-organic solvent catalysis is the most used biphasic catalytic process both in industrial an academic research due to, among others, the fact that water is a non-flammable, non-toxic and cheap solvent. The use of functionalized ligands with polar moieties is the most common strategy used to generate hydrosoluble catalysts. For instance, Ruhrchemie – Rhône Poulenc (nowadays Celanese AG) operates a continuous biphasic hydroformylation process based on the trisulfonated triphenylphosphine (TPPTS), which allows the separation and the reuse of the catalyst.[1]

It is well known that the strereoelectronic tuning of the ligands often leads to a dramatic optimization of a given catalyzed transformation. In spite of the well-established procedures developed to synthesize sulfonated phosphines, the number of examples of sulfonated phosphines with a strongly π-acidity is very scant.[2]

We will report the synthesis of a new family of disulfonated phosphines with the strong electrowithdrawing trifluoromethyl groups (DANPHOS type phosphines). [3,4] We will also report the performance of these new phosphines as ligands in the biphasic rhodium catalyzed hydroformylation of polar alkenes. Further studies on the activity, selectivities and the reuse of the catalyst will be presented, as well as a comparative study with other commercial sulfonated phosphines.

DANPHOS type phosphines (L)

References [1] E. F. Kuntz, Fr. Pat. 2.314.910, 1977, Rhône Poulenc [2] H. Gulyás, Z. Bacsik, A. Szöllósy, J. Bakos, Adv. Synth. Catal. 2006, 348, 1306. [3] D. Peral, J.C. Bayón, PCT Int. Appl., WO2011045417 (A1), 2011, Universitat Autònoma de Barcelona [4] DANPHOS type phosphines are available from Strem Chemicals, Inc. http://www.strem.com.

REF: FP5‐1


Mechanisms of olefin metathesis: reactivity and efficiency in the precursor activation and productive catalytic cycles

Francisco Núñez Zarur*, Xavier Solans Monfort, Luis Rodriguez Santiago, Mariona Sodupe Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain

*e-mail: [email protected]

Abstract Olefin metathesis is an important reaction in organic synthesis since it allows the easy formation of carbon-carbon double bonds. It is defined as the catalytic exchange between the substituent of two alkenes1, as shown in Scheme 1. One of the most common catalytic systems used today are Grubbs-Hoveyda-type catalysts, which are precursors of the real catalytic species and therefore need to be activated to enter the proper catalytic cycle. Several pathways for the precursor activation have been postulated (associative, dissociative, interchange)2, which are currently under debate. On the other hand, enyne metathesis is the catalytic coupling between an alkene and an alkyne to give a conjugated diene. For this reaction, the role of substituents in the enyne skeleton on the efficiency and selectivity during catalytic cycle has not been treated systematically. This work is devoted to two different important points of the ring closing enyne metathesis. (Scheme 2) First, we make use of Density Functional Theory (DFT) to determine the feasibility of the three proposed mechanisms for the precursor activation. Secondly, we focus on the catalytic cycle and, in particular, on the role of enyne substituents on the overall catalytic efficiency and selectivity. Our computational results indicate that the dissociative and interchange mechanisms are competitive, while the associative can be ruled out. At the same time, the styrene release is the rate-determining step3, independently of the mechanism taking place. In addition, this step can explain the experimental evidence satisfactorily and, more importantly, the knowledge of this step as the most important in the whole mechanism can help to design more active and faster catalysts. On the other hand, the ring closing metathesis of enynes generates two possible diene products (exo and endo, Scheme 2) and the efficiency and selectivity were found to be strongly dependent on the nature and position of substituents in the enyne skeleton. The knowledge of this selectivity is essential to lead the reaction towards one or another product. References 1 a) Handbook of Metathesis. R. Grubbs (Ed). Wiley-VCH: Weimheim, 2003; Vol. 1-3; b) K. J. Ivin, J. C. Mol, Olefin metathesis and metathesis polymerization; Academic Press: London, 1997; c) D. Astruc, New J. Chem., 2005, 29, 42; d) A. H. Hoveyda, A. R. Zhugralin, Nature, 2007, 450, 243. 2 V. Thiel, M. Hendann, K. J. Wannowius, H. Plenio, J. Am. Chem. Soc. 2012, 134, 1104. 3 a) F. Nuñez-Zarur, X. Solans-Monfort, L. Rodríguez-Santiago, M. Sodupe submitted; b) F. Nuñez-Zarur, X. Solans-Monfort, L. Rodríguez-Santiago, R. Pleixats, M. Sodupe, Chem. Eur. J. 2011, 17, 7506.

REF: FP5‐2

C

C

R3 R4

R2R1

C

C

R7 R8

R6R5 C C

R1

R2 R6

R5

+ +

C C

R3

R4 R8

R7

Scheme 1

RuCl

Cl

OR2

OR2

R5

precursor activación

NN R1R1

R3

R4

RuCl

Cl

NN R1R1

R5

R3

R4

catalytic cycle

Ring Closing Metathesis

O

precursor

active carbene

enyne

O

O

exoproduct

endoproduct

alkene

styrene

- Associative- Dissociative- Interchange

rate-determining step

Scheme 2


High sensitive lateral flow device for cadmium determination

A. López Marzo1,2, Josefina Pons2 , Diane A. Blake3 and Arben Merkoçi1,4,*

1 Nanobioelectronics and Biosensors Group, Catalan Institute of Nanotechnology, Campus de la UAB, 08193, Bellaterra, Barcelona, Spain

2 Department of Chemistry, Universitat Autonoma de Barcelona, 08193, Bellaterra, Barcelona, Spain. 3 Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA

70112 USA 4 ICREA, Barcelona, Spain,*E-mail: arben.merkoç[email protected]

Abstract As heavy metals have been demonstrated to have carcinogenic properties at high concentrations, they continue to be an important analyte for careful monitoring of the environment 1,2,3,4. Designing easy-to-use biosensors for trace metal ions in the environment has considerable importance as these metal ions are large in number, small in quantity and high in toxicity 4,5. Lateral flow devices are an ideal platform for making dipstick type tests. They are simple, portable, inexpensive, and use low sample volumes. Sensors based on paper are among the cheapest, and simplest to use 4,6. Specially cadmium is one of the most harmful heavy metal 3,6 and here a sensor based on lateral flow immunoassay for its detection in water has been developed. The principle of operation of this device is based on competitive reaction between the conjugated CdII-EDTA-BSA-AuNP (gold nanoparticles modified with CdII-EDTA-BSA) deposited on the conjugation pad strip and the CdII-EDTA complex in the sample of analysis through the sites of the CdII-EDTA-specific 2A81G5 monoclonal antibody7 that is immobilized onto the test line. The whole response range of the device was 0.4-2000ppb, being the linearity range between 0.4 and 10ppb Cd. The obtained detection limit of Cd is 0.1ppb which is 50 times lower than the maximum contaminant levels of Cd for drinking water as recommended by World Health Organization (WHO) and the Environmental Protection Agency (EPA)8. The integration of a second pre-conjugation strip within lateral flow platform with an adequate concentration of EDTA and OVA blocked the interference of other metals and permitted direct water sample analysis without the need of any previous treatment. The accuracy of the method was determined by evaluation of spiked drinking water samples. References [1] C. L. Schauer, M. Sanchen, R. R. Price, P. Schoen, F. S. Ligler, Environ. Sci. Technol., 2004,38,4409. [2] G. Aragay, J. Pons, A. Merkoçi, Chem. Rev., 2011,111, 3433. [3] M. Khosraviani, A. R. Pavlov, G. C. Flowers, D. A. Blake, Environ. Sci. Technol., 1998, 32, 137. [4] S. M. Z. Hossain, J. D. Brennan, Anal. Chem., 2011, 83, 8772. [5] D. Mazumdar, J. Liu, G. Lu, J. Zhou, Y. Lu, Chem. Commun., 2010, 46, 1416. [6] K. Abe, K. Nakamura, T. Arao, Y. Sakurai, A. Nakano, C. Suginuma, K. Tawaradae, K. Sasaki, J. Sci. Food Agric., 2011,91,1392. [7] D. A. Blake, P. Chakrabarti, M. Khosraviani, F. M. Hatcher, C. M. Westhoff, P. Goebel, D. E. Wylie, R. C. Blake, J. Biol. Chem., 1996, 271, 27677. [8] US Environmental Protection Agency, Risk Assessment, Management and Communication of Drinking Water Contamination, US EPA 625/4-89/024, Washington, DC, 1989. [9] K. Sasaki, S. Oguma, T. Glass, Y. Namiki, H. Sugiyama, N. Ohmura, D. A. Blake, J. Agric. Food Chem., 2008, 56, 7613.

REF: FP5‐3

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