CHE-313 - Gravity Waveschemistry.gravitywaves.com/CHE313L/CHE313SylManual_14.doc · Web viewMeasurement of the derivative's melting point and comparison with the known melting points

CHE-313 TENTATIVE SCHEDULE Spring '13

section topic reference

313-01 313-02

0. 1/21 1/22 No Lab HOLIDAY1. 1/23 1/24 check-in, orientation 2. 1/28 1/29 Nitration Exp’t., arene prep. supplement 3. 1/30 1/31 Arene Oxidation/IR & nmr supplement 4. 2/04 2/05 cont. IR/NMR SUP. 5. 2/06 2/07 cont. 6. 2/11 2/12 ID of unknown ketone C=OList 7. 2/13 2/14 cont. supplement 8. 2/18 2/19 No Lab HOLIDAY 9. 2/20 2/21 Reduct. of acetophenone supplement10. 2/25 2/26 cont.11. 2/27 2/28 Esterification supplement12. 3/04 3/05 cont13. 3/06 3/07 Grignard synthesis supplement14. 3/11 3/12 cont.15. 3/13 3/14 Aldol condensation SUP.16. 3/18 3/19 cont.17. 3/20 3/21 Diels Alder supplement18. 3/25 3/26 Diels Alder cont.19. 3/27 3/28 α,β-unsaturated ketone SUP.20. 4/01, 4/03 4/02, 4/04 No Lab SPRING BREAK .21. 4/08 4/09 α,β-unsaturated ketone cont22. 4/10 4/11 Lidocaine supplement23. 4/15 4/16 cont.24. 4/17 4/18 cont.25. 4/22 4/23 Qualitative analysis SUP.26. 4/24 4/2527. 4/29 4/3028. 5/01 5/0229. 5/06 5/07 30. 5/08 5/09 Written Quiz, Check-Out

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Pre-labs:

For each preparative lab you are required to submit at least 24 hours before the lab a pre-lab write-up. The pre-lab is to be written in your lab notebook and the carbon copies submitted for review. These carbon copies will later be attached to your lab report.

1. Title (be specific, eg. "Reduction of Acetophenone with Sodium Borohydride"), name & date.

2. Balanced chemical equation(s) for the reaction(s) that you are going to carry out.

3. Table of Physical Properties summarizing the physical properties of the reactants, solvents, and products. Make photocopies of the sample provided, or make up your own.

4. A step-by-step procedure for the reaction, separation, and purification. Be specific as to amounts (moles & weight or volume).

5. For multi-step syntheses prepare a separate Table of Physical Properties for each reaction in the sequence.

You may turn in pre-labs directly to the instructor or they may be placed in his mailbox in the Chemistry Office (NSM B-202). If you have not submitted a pre-lab before the lab you will not be allowed to begin the experiment until the pre-lab has been completed and okayed. Failure to submit pre-labs on time can severely affect your grade.

Lab Reports

A typed lab report is required for each experiment and is worth 20 pts (180 pts total) or approximately 45% of your total course grade. Reports are due one week after the scheduled completion of the experiment at 1:00 pm for section 01 and 9:00 am for section 02. Labs turned in after these times will be penalized 10% per day late.

Follow the following format for preparative reports:

1. Title, name & date (unknown #)

2. Balanced equation(s) for the reaction(s) you carried out.

3. Step-wise mechanism(s) for the reaction(s).

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4. Physical data for your product(s) (weight, mp or bp, %yield, & literature mp or bp for comparison).

5. Tabulation of spectral data. (Tables summarizing the IR and nmr spectra and your interpretation). see attached.

6. Conclusions, comments, deviations, etc. Discuss your results.

7. Answers to the questions at the end of each preparation.

8. Attach to the end of the report:

a) the pre-lab including table of physical properties

b) any additional carbon copies from your lab notebook

c) IR & nmr spectra, glc's, etc.

Products

With your lab reports you are to turn in the products that you have synthesized in the laboratory. Note, the labels must contain your name, the date, the identity of the contents, the net weight, and the mp or bp. Solid products should be in wide-mouth bottles and liquids in narrow-mouth containers.

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TABLE OF PHYSICAL PROPERTIES (This table must be completed before coming to lab!)

Reactants and MW Moles weight volume density bp mp solubility

solvents (g/mol) (g) (mL) (g/mL)(0C) (0C)

Product(s)

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TABLE OF PHYSICAL PROPERTIES (This table must be completed before coming to lab!)

Reactants and MW Moles weight volume density bp mp solubility

solvents (g/mol) (g) (mL) (g/mL)(0C) (0C)

Product(s)

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NITRATION OF A HALOARENE

NOTEWEAR GLOVES AND LAB COAT DURING THE ENTIRE PROCEDURE

Haloarenes and their nitration products are irritating to sensitive skin areas. If you should have these materials on your hands and then accidentally touch your face, this can cause a severe burning sensation in the affected area. If this should happen,

IMMEDIATELY:

1. Go to the restroom and wash the affected area with lots of soap and water. THE SOAP IN THE LAB IS NOT SUITABLE FOR THIS PURPOSE.

2. Return to the lab and apply mineral oil to the affected area.

3. The summary to this warning is NOT TO TOUCH ANY PART OF YOUR BODY WHILE PERFORMING THIS EXPERIMENT.

If you must leave the lab for any reason:

1. First dispose of your gloves in the waste container

2. Immediately go to the restroom and wash your hands thoroughly with soap and water.

AGAIN, LAB SOAP WILL NOT DO A SUFFICIENT CLEANING JOB

3. Upon returning to the lab, obtain another pair of gloves from the front of the room, and proceed with the experiment.

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NITRATION OF A HALOARENEEquation: H2SO4

RBr + HNO3 --------------> RBrNO2 + H2O

Locker # Compound1, 10, 20, 4 4 Bromobenzene2, 12, 22, 9 1,4-Dichlorobenzene3, 13, 19 1,3-Dichlorobenzene5, 15 1-Bromo-4-chlorobenzene 6, 16, 11 Chlorobenzene7, 17, 21 1,4-Dibromobenzene8, 18, 14 1,2 Dichlorobenzene

------------------------- FOR SAFETY REASONS --------------------------

1. Add 700mL of tap water to your 1 L Beaker. 2. Discard any acid washings, plus the contents of the filter flask (from step 9 below) into your

1 L Beaker, WITH STIRRING. 3. Wash the contents of your 1 L Beaker down the sink.

PROCEDURE

1. Obtain 0.025 mole of your haloarene ( See table above ) to a small beaker/graduated cylinder, and place it in yourhood area.

2. Prepare a mixture of 5 mL conc HNO3 and 5 mL conc H2SO4 in a 25x150 mm test tube, take it back to your hood workstation and clamp it to your hotplate/stirrer, immersing the tube in a 150 mL beaker containing 100 mL tap water. Allow the tube to cool to 30 deg. C, measured using your glass thermomtter.

3. To the test tube, add your haloarene, gently stirring to mix the contents. Continue to stir/agitate the test tube contents until the haloarene begins to transform into solid nitrohaloarene immersed in the acid mixture. Keep the reaction mixture between 50 - 55 oC. DO NOT ALLOW THE REACTION MIXTURE TO EXCEED 60 o C .

4. After the exothermic reaction has subsided, heat the test tube for 10 min. on your hot plate set at ~ 2.5 to maintain the temperature below 60oC during this period.

5. Cool the test tube in an ice bath to room temperature

6. Pour the reaction mixture into 50 mL of distilled water which is in a 150 mL beaker.

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7. Isolate the crude product by vacuum filtration.

8. Wash the filter cake thoroughly with cold (0-10oC) distilled water and dry the filter cake by allowing the vacuum apparatus to draw air through it after you have finished washing.

9. Place the washings into the 1L beaker. Transfer the crystals to a TARED 50 mL beaker and obtain the weight of your wet product

10. Calculate the volume of 95%(v/v) ethanol needed to just dissolve the halobromobenzenes. You will need approx. 5 mL 95% ethanol per gram of crude product. Round the amount of ethanol needed to the next 5 mL increment. (e.g.: 5.6 g. x 5 mL/g = 28 mL => use 30 mL). SHOW THIS CALCULATION IN THE PROCEDURE PORTION OF YOUR REPORT.

11. Bring this mixture to boiling to dissolve the crude product. If the product does not completely dissolve boiling, add 5 mL of 95%(v/v) ethanol. If solid still remains you will have to do a hot filtration. Once your crude product has dissolved, set the flask onto your lab bench and allow the contents to cool slowly to room temperature.

12. Isolate the nearly pure crystals of your product by vacuum filtration. If there is solid material in the filter flask at this point, pour it into a beaker and vacuum filter this solution again through the funnel containing the first crop of nitrobromobenzene. Save the filtrate.

13. Wash the crystals with a little ICE COLD ethanol, allowing the washes to drain into the filter flask containing the filtrate. The filtrate may now be poured into the recovered organic solvents container at the east end of the lab.

14. Allow air to be drawn through the Buchner funnel for 5 min. then detach the vacuum hose from the filter flask, turn off the water and transfer the solid from the Buchner funnel onto 11cm filter paper which is on a watch glass. Spread the solid over most of the filter paper, breaking large clumps into small particles and put it in your drawer to dry overnight. Place another piece of filter paper lightly over the crystals to keep the dust out.

Thin - Layer Chromatography

1. Take a few crystals of haloarene isomer, place in a 5 ml beaker, and add 5 drops of acetone to the beaker to dissolve the crystals. Do the same with your known haloarene standards

2. Take a 2.5 x 7.5 cm strip of silica gel, mark the origin 1 cm from bottom and make 2 pencil marks lightly on the origin.

3. Apply one drop of the solution containing the 4-nitro isomer on one spot & one drop of oil containing the 2-nitro isomer on the other spot. Be sure that neither application results in a spot more than 2 mm in diameter. Allow the strip to dry at your hood workstation .

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4. Place dried strip in jar containing the solvent solution Hexane: Chloroform 9:1.

5. When the solvent system reaches within 1 cm of the top of the strip, remove the strip, allow to dry at your hood workstation & view under ultraviolet light in the U.V. box. Outline the spots with a pencil by stippling around each spot while the chromatogram is still in the U.V. box.

6. Dispose of the remainder of your product into the jar provided at the front of the lab.

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Infrared Spectroscopy

The natural frequencies of vibration of covalently bonded atoms correspond to radiation frequencies that lie in the infrared region of the electromagnetic spectrum. If infrared radiation is directed at an organic molecule, one of whose vibrational frequencies is the same as the frequency of the radiation, that radiation is absorbed to some degree and vibration is stimulated. The radiant energy absorbed is equal to the difference on the energies of the vibrational levels: ΔE = hv. In order for interaction with infrared radiation to occur, it is essential that the electronic dipole moment of the absorber vary during the course the vibrational motion. Thus not all vibrational modes are active in the infrared spectrum.

Particular vibrational modes (and their associated infrared absorption frequencies)can often be identified with a specific molecular fragment. In many cases organic functional groups constitute such fragments.

Vibrational modes can be divided into two general catagories: stretching and bending modes. These modes can be further differentiated into asymmetric and symmetric stretching and rocking, scissoring, twisting and wagging, which are associated with bending.

Table of IR Absorptions

Functional Group

Characteristic Absorption(s)

(cm-1)Notes

Alkyl C-H Stretch

2950 - 2850 (m or s)

Alkane C-H bonds are fairly ubiquitous and therefore usually less useful in determining structure.

Alkenyl C-H Stretch

Alkenyl C=C Stretch

3100 - 3010 (m)1680 - 1620 (v)

Absorption peaks above 3000 cm-1 are frequently diagnostic of unsaturation

Alkynyl C-H Stretch

Alkynyl C=C Stretch

~3300 (s)2260 - 2100 (v)

Aromatic C-H Stretch

Aromatic C-H Bending

~3030 (v)860 - 680 (s)1700 - 1500

(m,m)

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Aromatic C=C Bending

Alcohol/Phenol O-H Stretch

3550 - 3200 (broad, s)

See "Free vs. Hyrdogen-Bonded Hydroxyl Groups" in the Introduction to IR Spectra for more information

Carboxylic Acid O-H Stretch

3000 - 2500 (broad, v)

Amine N-H Stretch 3500 - 3300 (m)

Primary amines produce two N-H stretch absorptions, secondary amides only one, and tetriary none.

Nitrile C=N Stretch 2260 - 2220 (m)

Aldehyde C=O Stretch

Ketone C=O Stretch

Ester C=O Stretch

Carboxylic Acid C=O StretchAmide C=O

Stretch

1740 - 1690 (s)1750 - 1680 (s)1750 - 1735 (s)1780 - 1710 (s)1690 - 1630 (s)

The carbonyl stretching absorption is one of the strongest IR absorptions, and is very useful in structure determination as one can determine both the number of carbonyl groups (assuming peaks do not overlap) but also an estimation of which types.

Amide N-H Stretch 3700 - 3500 (m)

As with amines, an amide produces zero to two N-H absorptions depending on its type.

Nuclear Magnetic Resonance Spectroscopy ( NMR )

Unlike Infrared and Ultraviolet spectroscopy, Nuclear Magnetic Resonance Spectroscopy requires exposure of the organic substance to the radiofrequency portion of the electromagnetic spectrum while the substance is simultaneously subjected to a strong external magnetic field. Certain atomic nuclei have magnetic properties, and thus absorption or emission of energy by the nuclei may occur. The hydrogen atom is the simplest atom containing nuclei having a magnet moment. A spinning proton posses a magnetic moment which may be aligned with or against an externally applied magnetic field. Protons whose spin magnetic moments are aligned with the field

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http://www.chem.ucla.edu/~webspectra/irintro.html

http://www.chem.ucla.edu/~webspectra/irintro.html#hydroxyl

http://www.chem.ucla.edu/~webspectra/irintro.html#hydroxyl

are in a more stable ( lower energy ) state than those whose spin magnetic moments are antiparallel to the applied field.

Chemical Shift

Not all of the hydrogen nuclei in a molecule respond to the same degree when effected by a circulating magnetic field. We use this principle to differentiate between one type of hydrogen molecule, from one in a different location/environment. The actual location in the spectrum is arbitrarily aligned to a zero reference point – tetramethylsilane( TMS ), which is assigned a value of 0 ppm. A mixture of an organic compound dissolved in a 5% TMS in CCl4 solution will yield an NMR spectrum where the peaksare the hydrogen nuclei reacting to the NMR magnets magnetic field. These chemical shifts correspond to particular types ho hydrogen nuclei in their specific orientation/environment within the molecule. The magnitude of the chemical shift depends very much upon the electron density in the area of the proton. Chemical shift tables should be used as a general guide, since combinations of effects of neighboring structures can affect a protons shift slightly.

Spin-Spin Splitting

More complex molecules yield spectra where the total number of peaks observed is far greater than the number of different hydrogens present. The multiplicity of peaks grouped together is a consequence of the interaction of the magnetic fields associated with one type of hydrogen with those of nonequivalent neighboring hydrogens, a phenomenon known as coupling. The net effect usually is the splitting of the signal into n + 1 smaller closely spaced peaks, where n is the number of adjacent hydrogens that are equivalent to one another.

CHE-313 Reporting IR and nmr spectra

Report the results of infrared and nmr spectroscopy in tabular form. See example below:

For the nmr:

1. Draw the structure of the compound and label the groups of hydrogens that give rise to each signal using a, b, c ... (let a = most up-field).

2. Make a table showing the chemical shift, integration and splitting pattern for each group of hydrogens assigned to the structure.

example: ethoxybenzene Ph-O-CH2CH3 c b a

a 1.3 ppm 3H triplet

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b 3.9 ppm 2H quartet

c 6.6-7.2 ppm 5H complex

For the IR:

Make a table listing in decreasing order all of the absorbances and identify those that are important.

example: ethoxybenzenefrequency (cm - ) interpretation

3040 C-H stretch unsaturation, Ar-H30002940 C-H stretch saturation1600 C=C stretch, aromatic ring15801500 C=C stretch, aromatic ring1480 C-H bend, saturated1390 " " "1300124011701120 C-O stretch, ether1050 880 800 C-H out of plane bend - 750 mono-substitution 690

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Oxidation of a side chain & introduction to IR and nmr

You will oxidize an unknown arene with KmnO4 to a benzoic acid. See the procedure in this supplement. Because the starting material is an unknown, the table of physical properties is a little different from the ones you have previously prepared. You will be given (on the unknown bottle) the molecular formula of your unknown. Calculate the gram formula weight and the number of moles contained in 1.0 grams. The amount of KMnO4 you will use is based on the formula of your unknown.

You will identify the unknown arene from the melting point of the acid product and the IR and nmr spectra of the unknown. Be sure to balance your chemical equations correctly. No mechanism is required for this report. Include the answers to the following questions in your report.

Answer the following questions:

1. Write a balanced chemical equation for the permanganate oxidation of p-xylene under basic conditions. See your general chem text for review of balancing oxidation-reduction equations.

2. Write a balanced chemical equation for the permanganate oxidation of tolune.

3. Write chemical equations to show how you would oxidize toluene to benzaldehyde rather than benzoic acid. see M&B

4. Why is benzoic acid more soluble in base than in aced?What is this difference in solubility used for?

5. Tert-butylbenzene is not oxidized by permanganate to benzoic acid. Why not?

6. a) Draw all of the arenes with formula C7H7Br and show the products of oxidation for each one. b) Look up the mp of each product. c) Can you identify every isomer based on the melting point of the carboxylic acid derivative? Explain.

7. Write a balanced equation for the reaction of potassium permanganate with sodium bisulfite.

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Identification of an unknown arene by oxidation to the carboxylic acid; introduction to IR and nmr spectroscopy.

A classical approach to the identification of some aromatic compounds is the oxidation of side chains to carboxylic acid groups. Measurement of the derivative's melting point and comparison with the known melting points of different benzoic acids provided a means of identifying or eliminating certain possible structures. For example: if a compound was found to have the formula C8H10, it could be four different compounds: ethyl benzene, o-xylene, m-xylene, or p-xylene. If you look up the boiling points of these four compounds, they are very close to each other. On the other hand, the melting points of the corresponding carboxylic acids produced from the oxidation of the side chains are distinctly different. When combined with additional information, such as the IR and nmr spectra, the melting point of the derivative will usually be sufficient to determine the structure of the unknown.

You will be given a small sample of an unknown arene for which the only information provided is the molecular formula. You are to carry out the permanganate oxidation in alkalai solution and isolate the carboxylic acid. You will measure the melting point of the acid and compare it to the melting points of the possible derivatives from your molecular formula. In addition, you will obtain the IR spectrum of your original uknown and the nmr spectrum.procedure:1. The apparatus consists of a 250 mL round-bottom flask fitted with a reflux condenser.2. Place about 1 gram (40 drops) of the unknown into the flask.3. Add approx. 80 mL of water and 1-2 mL of 6M NaOH to the flask.4. Using the powder funnel, introduce the required amount of potassium permanganate (see table below) into the flask and add a couple of boiling chips.

compound formula g KMnO4/g unknownC7H8 4 gC8H10 6 gC9H12 8 g

5. Attach the reflux condenser and begin heating the mixture with a heating mantle. Be careful when the mixture first starts to boil as it has a tendency to "bump".6. Continue the reflux for 2-3 hours. At the end of the first period, cool the flask, label it, cork it, and place it in one of the hoods until next lab.7. Suction filter the contents of the round-bottom flask to remove the solid MnO2.8. Transfer the filtrate to a 250 mL beaker. Place the beaker in a ice bath, and after the solution has cooled for 10 minutes, acidify with 10 mL of 6 M H2SO4, while stirring. (If the solution is still purple due to excess permanganate, destroy it by adding no more than about 2 mL of 20% sodium bisulfite.9. Test the solution with litmus to verify that it is acidic; if not add more sulfuric acid.10. Filter the precipitated acid with suction through a small buchner funnel and wash with a few mL of cold water. (If no acid has precipitated, consult with the instructor). 11. Recrystallize the acid from a suitable solvent (try water first).12. Let the product air dry, weigh it, package it, and obtain its melting point.

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Identification of an unknown carbonyl

In this experiment you will be given an unknown aldehyde or ketone. You will obtain the IR and nmr spectra, do the Tollen's test, and prepare two solid derivatives. In the report, identify the unknown and compare the experimental values with the ones given in the text; make a TABLE for comparison. Be sure to include balanced equations for the Tollen's test, the preparations of the derivatives, as well as appropriate mechanisms. Do not weigh derivatives or calculate % yield.

Prepare the 2,4-dinitrophenylhydrazone derivative of your unknown. The reagent is already prepared. Mix 10 drops (0.5 mL) of your unknown in 20 mL of 95% ethanol. To this solution, add 15 mL of the 2,4-DNPH reagent. Shake the mixture vigorously. If a precipitate does not form immediately, let it stand for 15 minutes. Suction filter the solid derivative and recrystallize from 95% ethanol. After air drying, obtain the mp.

Make an additional derivative, the semicarbazone, according to the directions on page 1014 and obtain the mp.

Test the unknown with Tollen's Reagent (p 494) to see if it is a ketone or an aldehyde. Page 1000-1001 lists possible aldehydes in increasing order of boiling point and the melting points of easily prepared derivatives. Ketones are listed in the table on pages 1001-1003.

Do a simple distillation to measure the boiling point of your unknown carbonyl compound.

Obtain the IR and nmr spectra of your unknown carbonyl compound.

Answer the following questions:1) An unknown organic compound (b. 212-216 oC) gives a positive 2,4-DNPH test and is

positive with Tollen's reagent. A semicarbazone derivative is made that melts at 228-232 oC. What is the identity of the unknown? What would you do next?

2) Predict the products of the reaction of the following with silver nitrate in ammonium hydroxide:

cylcohexanoneformaldehydeacetoneacetophenonebutyraldehyde

3) In the reaction of an aldehyde or ketone with derivatives of ammonia, the reaction can be catalyzed by sulfuric acid. However, it is important that the pH not be too low since the reaction will slow down at very high acid concentrations. Explain.

4) Ketones do not oxidize readily. However, cyclohexanone will react with powerful oxidizing agents at high heat to adipic acid (HO2C-(CH2)4-CO2H). The reaction is not really one of the ketone, but the enol. Write equations to show how this is possible.

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Reduction of acetophenone to 1-phenylethanol

- 0.5 g NaBH4 + 10 mL EtOH (95%)

- dropwise (controlled addition; keep temperature < 50o ) of 5 mL of acetophenone

- let stand 15 minutes

- acidify with 5 mL (6M) HCl

- boil down on hot plate until you have two layers

- extract with (1) 20 mL Et2O (2) 10 mL Et2O

-dry combined ether extracts over anh. MgSO4 TWICE!

-distill off Et2O ( waste bottle )

-residue = crude product (bp 102.5 – 103.5 @ 19 Torr), do not distill

IR, nmr of product AND acetophenone

We will not purify the product with vacuum distillation. After the removal of the diethyl ether, package, weigh and label the crude product. Obtain IR and nmr on both the acetophenone and the product.


1. What was the molar ratio of NaBH4 to acetophenone that you used in the experiment. What is the theoretical ratio? Why did you use more than the theoretical ratio?

2. After the reaction of the carbonyl with sodium borohydride, the mixture is treated with water and acid to produce the desired alcohol. Indicate the source of the alcoholic hydrogen in the product.

3. Although sodium borohydride reacts slowly with methanol, when mineral acid was added, it rapidly decomposed with the evolution of hydrogen. Explain.

4. Why is 1-phenylethanol more prone to dehydration than 2-phenylethanol?

5. What is the structure of the white precipitate that forms in the reaction of acetophenone with NaBH4?

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6. Write an equation for the reaction of the white ppt with water and HCl.

7. Draw the structure of the products of the reduction of each of the following with NaBH4:

a) cyclohexanoneb) 3-cyclohexen-1-onec) 1,4-butanediald) 4-oxohexanal

8. Draw the structure of the products for the reduction of each of the compounds in question 7 with excess hydrogen gas over Nickel.

9. Why does the concentration of the ethanolic reaction mixture, followed by the addition of HCl, result in the formation of two layers?

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EsterificationPREPARATION OF METHYL BENZOATE

1. Take your 100-mL round-bottomed flask, cork ring and wide stem funnel to one of the lab balances and add 10-gm benzoic acid, followed by 25-mL methanol.

2. From the repipettor, carefully add 3-mL conc. H2SO4 down the side of the flask.

3. Swirl the flask to mix the reagents. Add your magnetic stirring bar to the flask.

4. Attach a reflux condenser, and gently reflux for one hour.

5. Transfer the solution in the flask to a 250-mL separatory funnel containing 50-mL water.

6. Rinse the flask with 40-mL diethyl ether and add the rinsing to the funnel.

7. Shake the funnel thoroughly, ( venting the funnel frequently ), to facilitate extraction of the methyl benzoate into the ether layer.

8. Remove the aqueous layer and wash the organic layer with a second 25-mL portion of water.

9. Separate the layers, (leaving the organic layer in the funnel), and cautiously add 25-mL 0.6M NaHCO3 to the organic layer remaining in the funnel.

10. Shake the mixture, (venting frequently), to wash the product of any remaining acids. ( Which acid(s) ?).

11. Remove the aqueous layer and test to see it is basic to litmus. If not, Wash the organic layer with another 25-mL portion of NaHCO3 and test the aqueous wash again with litmus.

12. Once the NaHCO3 wash is basic to litmus, wash the organic layer a final time with Saturated NaCl. (why ?).

13. Dry your product over anhydrous MgSO4.

14. Decant the dried organic layer into your 100-mL round-bottomed flask and simple distill off the remaining ether - hotplate set at 3.

15. Allow the flask to cool and weigh the product.

16. Save this product for use in the Grignard Experiment.

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Answer the following questions as part of your report:

1) a) If the Keq for the esterification of acetic acid with isopentyl alcohol is 3.0, what is the maximum amount of isopentyl acetate that can be recovered at equilibrium if a 1:1 mole ratio of acid:alcohol is used?

b) If a 1:5 mole ratio is used?c) 5:1 mole ratio?

2) What role does sulfuric acid play in this reaction? Explain; show equations.

3) Tell what effect doubling the concentration of sulfuric acid would have on the yield of the ester.

4) Why were the contents of the round bottom flask after reflux poured into 10 mL of water?

5) Why do we wash the ester with sodium carbonate solution?

6) Why would solid NaOH not be a good drying agent for the ester?

7) How would you distinguish between the nmr spectra of methyl benzoate and phenyl acetate?

8)

Organometallics

Glassware to be used in Grignard Reaction

Your 250-mL round-bottomed flask, claisen connecting tube, condenser, 2 test tubes, and 125-mL separatory funnel, should be dry. Leave it out on your desktop for.

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PREPARATION OF TRIPHENYLMETHANOL

H2SO4(aq)Eq: 2Mgo + 2C6H5Br + C6H5COCH3 ------------------> (C6H5)3· COH + CH3OH + 2Mg+2 + SO4

-2 + 2Br

Amounts of reactants actually used and maximum amounts possible of product

Compound Mgo C6H5Br C6H5COOCH3 (C6H5)COH

MW 24.0 157 136 260

Moles

Grams 2.4

Density (g/ml) 1.522 1.094

ml - 12.4 5.6

MPoC - -31 -12.4 164

BPoC - 156 196 -

Assemble your apparatus as shown in the lab demo.

1. Working quickly, bring your reaction flask to the front of the room and add to it 2 shots (10 mL) of ANHYDROUS diethyl ether, and the contents of the vial of Mg provided.

2. Reassemble your reaction flask to your apparatus.

3. Take your separatory funnel (with stopcock CLOSED ) to the front of the room and add to it 3 shots (9.3 mL) bromobenzene and 5 shots (25 mL) diethyl ether. Swirl the funnel to mix its contents and reassemble the funnel to your apparatus.

4. Prepare an ice bath in case it is needed.

5. Begin water running through your condenser.

6. Start your magnetic stirrer and add a 2- to 3-mL portion of the funnel contents to your reaction flask.

7. Take the dried test tube to the front of the room and add to it 1 shot of bromobenzene and 1 shot of ether.

8. Add enough magnesium turnings to barely cover the bottom of the tube.

9. With a stirring rod or spatula mix the contents of the tube.

10. Scrape the magnesium against the bottom and the sides of the tube frequently, to promote reaction between the bromobenzene and the magnesium.

11. Once the reaction has started, the ether will begin to reflux, and the tube will become warm to the touch, and subsequently the solution will turn brown.

12. At this point quickly remove your separatory funnel and add the contents of your tube to your flask. Return the 21

separatory funnel to apparatus. When the contents of the flask begin to reflux, start adding the rest of the contents of your separatory funnel DROPWISE at a rate just fast enough to allow one drop of ether to fall from the condenser tip into this flask every second. Adding the contents too quickly causes coupling and overheating (see "explanations of procedure"). If the reaction becomes too vigorous, cool the reaction flask with your ice bath and reduce the rate of addition from your separatory funnel. If the reflux becomes too slow heat the reaction flask gently by cupping you’re your hands around the flask. The entire addition should be finished in 30 minutes.

13. Allow the reaction to proceed until only a few slivers of Mgo remain (about 2 hrs.). The contents of the flask now should be milky brown.

14. Once the Grignard Reagent has cooled to room temperature, add 5.6 mL of Methyl Benzoate and 20 mL anhydrous diethyl ether to your dropping funnel.

15. Begin s l o w, dropwise addition of the contents of the dropping funnel to the reaction flask. As in the preparation of the Grignard Reagent, control the rate of reaction by adjusting the rate of addition from the dropping funnel, and occasional icing of the reaction flask, should it become necessary. When the reflux has stopped the mixture may be heated to reflux for another 30 minutes to finish the reaction. Cool the flask, and once cooled to room temperature, stopper it.

Return any excess Methyl Benzoate to the recovery bottle at the end of the west bench.Failure to turn in your remaining methyl benzoate to the proper recovery container will result in a 5 point reduction in your lab report score.

DAY 2

16. Your reaction flask should contain approx. 100 mL of a solid/liquid mixture. IF NOT, add additional diethyl ether to bring the volume to about 100 mL.

17. In a 250-mL Erlenmeyer flask add enough ice to cover the bottom of the flask, followed by 50 mL of 6M H2SO4 - swirl the ice-acid mixture.

18, Add the contents of the reaction flask to the erlenmeyer, with swirling. Continue swirling until all solid matter has dissolved, and the solution is homogeneous. If there is still solid in the upper ether layer, continue adding ether and swirling the flask until all of the solid has dissolved.

19. Transfer the mixture back into the reaction flask, to collect any solid left behind.

20. Transfer this solution to a 250-mL separatory funnel and shake it vigorously but carefully, with frequent venting. If solid persists, add aliquots of ether.

21. Remove the aqueous layer from the funnel and pour the organic layer back into your reaction flask

22 Return the organic layer to your separatory funnel and wash the organic layer with 10 mL of 3M H2SO4.

23. Remove the aqueous layer from the funnel and wash the organic layer with 10 mL of saturated NaCl.Test this aqueous layer with blue litmus paper. If the paper turns red, repeat step #23 until the NaCl aqueous layer no longer tests acidic to blue litmus paper.

24. Dry the organic layer with anhydrous Na2SO4, and decant it into a 150 mL beaker.

25. Add a boiling stick to the beaker, and boil off the ether on your hot plate set at "2”. The Triphenylmethanol remains in the flask. Pour your aqueous phases down the drain.

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26. Recrystallize the residue from your beaker, using a 2:1 mixture of cyclohexane:Absolute Ethanol; as follows:

a. Place 40 mL of the solvent mixture into a 100 mL beaker.

b. Place the beaker with solvent onto a hotplate and allow it to come to a boil. DO NOT ADJUST THE HEAT SETTING ON THE HOT PLATE - LEAVE IT AT "2"

c. Remove the beaker of boiling solvent off the hot plate and add just enough solvent to dissolve the

contents of your flask (swirl the flask contents during solvent addition, to insure only a minimum of solvent is used to dissolve your crude product.). The remainder of the solvent is to be iced, to wash your crystals.

d. Transfer the contents of your flask to a 100 mL beaker. Allow your product to cool to room temperature on your desktop.

e. Place the beaker in an ice bowl, to recrystallize your product.f. Vacuum filter the contents of the beaker, to recover your product.

g. Wash your product with a small portion of ice-cold solvent.

h. Leave the vacuum on for an additional 5 minutes, to help dry your product.

i. Detach the hose from the filter flask then turn off the vacuum and place your product into your drawer to dry overnight.

27. Weigh your product and determine its melting range. Put these data in the results of your notebook and laboratory report.

28. Place your product in the jar provided at the end of the west bench.Failure to turn in your remaining product to the proper recovery container will result in a 5 point deduction from your lab report score.


1) Why must all equipment be dry when reacting tolyl magnesium bromide with carbon dioxide? (show equations)

2) a) Explain the difference between "inverse" and "normal" addition of organometallics and substrates.

b) Which was done in this experiment? Why?

3) Write chemical equations to show all of the different methods that can be used to synthesize tertiary alcohols with Grignard reagents.

4) Write all steps in the mechanism for the reaction of an ester with a Grignard reagent.

5) What side reactions are possible during the formation of a Grignard reagent? Write structures. How were these separated from the product?

Answer questions 1, 2, 5 on page 314.

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Aldol condensation

You are to prepare anisalacetophenone (AKA 4-methoxychalcone) via an aldol condensation Using the following protocol. You will recrystallize the crude product from 95% ethanol. Run the nmr and IR (CCl4) spectra of your product.

Transfer 0.65 mL p-anisaldehyde to a tared 50-mL Erlenmeyer flask and reweigh the flask to determine the weight of the material transferred.

Add 0.60 mL acetophenone and 4.0 mL of 95% ethanol to the flask and swirl to mix the contents and dissolve any solids present. If the solids do not dissolve after about 5-10 minutes of swirling, heat the flask on a hotplate set at 2-3 and srirl until solid is dissolved.

The contents of your flask should be at room temperature before adding one pellet of NaOH to the flask.

Swirl the flask until a solid forms.

Add 10 mL of ice water to the flask and stir the mixture with a spatula to break up any clumps of solid present.

Transfer the mixture to a beaker containing 15 mL of ice water and stir the mixture with a spatula to break up any clumps of solid present.

Vacuum filter, and wash the filter cake with a small portion of ice-cold water.

Allow the product to dry overnight before obtaining its melting point.

Save your product..

answer the following questions:

1) In the aldol condensation you ran:a) Why doesn't the ketone undergo a self-condensation?b) Why doesn't the aldehyde undergo the Cannizzaro reaction?c) Write equations for both of the above reactions.

2) Are there geometric isomers of the product of this synthesis? Draw them. Is the reaction stereoselective or stereospecific? Which product is actually formed and why.

3) Predict the products of the following:

a) butyraldehyde, dil. NaOH

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b) formaldehyde, conc. NaOHc) acetone, p-tolualdehyde(2 mol), dil NaOHd) 2,2-dimethylpropanal, formaldehyde, conc. NaOHe) benzaldehyde, methyl acetate, sodium methoxide

4) Why does the intermediate in the synthesis undergo spontaneous dehydration?

5) Show the stereochemistry of the hydroxylation with potassium permanganate of trans- anisalacetophenone using Fischer projections.

Answer question 4 on page 325 of your lab text.

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Diels Alder

Run the Diels Alder condensation reaction between alpha-phellandrene and maleic anhydride according to the directions below. Obtain IR (KBr pellet) spectrum of the product.

Write up a pre-lab for the condensation of α-phellandrene (2-methyl-5-isopropyl-1,3-cyclohexadiene) and maleic anhydride.You won't find the product in the CRC.

The α-phellandrene that we have is not pure, it only contains 70% α-phellandrene by weight. You will need to figure how much of the impure compound to weigh out that will contain 0.050 mole of the α-phellandrene.

In a 100-mL round-bottom flask put 0.050 mole of maleic anhydride and the weight of impure α-phellandrene that contains 0.050 mole. Add 25 mL of ethyl acetate, attach a reflux condenser, and heat on a hot water wath for one hour. Cool in an ice-water bath and then suction filter. Recrystallize the product from ethyl acetate, vacuum filter, let air dry, weigh, package, and obtain the IR spectrum (KBr method).

Put all remaining product into the recovery bottle provided at the front of the lab.

answer the following questions:

1) Why is the endo product usually preferred in Diels-Alder condensations?

2) In your product, which way is the isopropyl group pointed? Explain.

3) The product of your synthesis has three chiral centers. Draw the product and label each chiral center with and asterisk (*). How many stereosiomers are theoretically possible? Only one stereoisomer is actually formed in this reaction, explain.

4) Predict the products of the following:

a) 1,3-butadiene + 2-butyneb) 1,3-cyclopentadiene + cis-2-butenec) 1,3-butadiene + dimethyl maleate(methyl ester of maleic acid)d) (2 mol)1,3-cyclopentadiene + p-benzoquinonee) dicylopentadiene + heat (retro Diels-Alder)

5) Explain why the diene must be in the sigma-cis conformation in order to undergo a Diels-Alder reaction.

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Preparation of an α,β-unsaturated ketone via Michael Addition combined with an aldol condensation .

Day 1

Add 1.2 gm of your aldol product, 0.75 gm ethyl acetoacetate and 25 mL 95% ethanol to a 50 mL RBF.

Swirl to dissolve the flask contents.

Add your magnetic stirrer and one pellet of NaOH to the flask.

Equip the flask with a reflux condenser and heat at a gentle reflux for 60 mins.

Allow the flask contents to cool to room temperature, then add 10 mL of H2O and stir/scratch the bottom of the flask with a stirring rod to promote crystallization.

Cool the flask in an ice bath and vacuum filter the flask contents, washing the flask and crystals with 4 mL of ice water.

Rinse the flask with an additional 3 mL of ice-cold 95% ethanol and pour this over the drying crystals in your Buchner funnel.

Day 2

Transfer your crude product to a 100 mL beaker and add 7 mL acetone. Stir with a spatula to dissolve any solid present. Add additional aliquots ( 1 or 2 ) of acetone, if necessary, to dissolve the solid.

Decant the liquid into a large test tube and centrifuge for 2-3 minutes.

Decant the liquid into a tared 50-mL Erlenmeyer flask and evaporate the acetone by heating on a hotplate set at 1-2, blowing a gentle stream air into the flask.

Your flask should contain a solid product. If you have an oil, scratch the bottom of the flask with a stirring rod to promote crystallization.

Weigh the flask to determine the amount of product obtained.

Recrystallize the product with 95% ethanol.

Vacuum filter. Wash the flask and product with 3 1 mL portions of ice-cold 95% ethanol.

Weigh. Mp.

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Put all remaining product into the recovery bottle provided at the front of the lab.

You will obtain the IR spectrum of the product.

Answer the following questions :

1. Draw a mechanism for the enamine synthesis of Δ1,9-2-octalone.Why is this octalone rather than the Δ9,10-2-octalone the main reaction product ?Why is there a substantial amount of Δ9,10-2-octalone produced ?

2. (a) The enamine formed from pyrrolidine and 2-methylcyclohexanone has the A structure. Why is the less substituted enamine being formed rather that the more substituted B ?

A B

(b) Draw the structure that would result from the reaction of enamine A with methyl vinyl ketone. Compare its structure with the product obtained in question 3.

3. (a) The enolate formed from 2-methylcyclohexanol has the following structure. What is the structure of the other possible enolate, and why is it not as stable as the one shown ?

(b) Draw the structure of the product that would result from the reaction of methyl vinylketone. Compare its structure with the product obtained in question 2.

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4. Draw the structures of the Robinson annelation products that would result from the following reactions:

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Lidocaine

You will synthesize lidocaine via a series of synthetic reactions according to the instructions below. A single report is required with IR and nmr spectra of the final product. Be sure to calculate % yield for each step of your synthesis as well as the overall % yield.

multistep synthesis of lidocaine

first lab:

Reduction of 1,3-dimethyl-2-nitrobenzene to 2,6-dimethylaniline

Ar-NO2 + SnCl2.2H2O, HCl ---> Ar-NH3

+,Cl- + SnCl4

-make up the following two solutions:

solution 1: 0.10 mole (22.6 g) SnCl2.2H2O in 40 mL of conc. HCl (warm to dissolve)

solution 2: 0.033 mole (5 g, 4.5 mL) 1,3-dimethyl-2-nitrobenzene in 50 mL acetic acid

-mix the two solutions and let stand for 15 minutes

-after fifteen minutes, cool in ice bath and vacuum filter

Ar-NH3+,Cl- + KOH ---> Ar-NH2

-tranfer solid to a flask and add 25 mL of water, make strongly basic with 40-50 mL of 8M KOH (caution!)

-cool to room temperature with ice bath

-extract with (1) 25 mL diethyl ether(2) 10 mL diethyl ether

-wash combined ether extracts with 10 mL water; repeat

-dry over anh. K2CO3

-filter into pre-weighed RB flask and remove diethyl ether by distillation (ether --> waste bottle)

-reweigh flask

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α-chloro-2,6-dimethylacetanilide

Ar-NH2 + Cl-CH2COCl ---> Ar-NHCOCH2-Cl

-residue from above + 25 mL acetic acid

-add (3.7 g, 2.6 mL) α-chloroacetyl chloride (caution!)

-warm to 40-50oC

-add solution: (5 g NaO2CCH3.3H2O in 100 mL water)

-cool, vacuum filter, air dry, weigh, mp

second lab:

lidocaine

Ar-NHCOCH2-Cl + NH(CH2CH3)2 Ar-NHCOCH2-N(CH2CH3)2

-note: all reagents and apparatus must be dry!

-in a 250 mL RB flask, combine the α-chloro-2,6-dimethylacetanilide from above with 45 mL toluene

-calculate the number of moles of α-chloro-2,6-dimethylacetanilideand add three times that number of moles of diethylamine to the RB.

-attach a water cooled condenser and reflux for 90 minutes.

-cool in an water bath and vacuum filter off the solid that forms. (this is not your product!)

-transfer the filtrate to a separatory funnel and extract with two 25 mL portions of 3M HCl.

-combine the aqueous layers in a 250 mL Erlenmeyer flask and add 50 mL of 8 M KOH to make the solution stronly basic.

-warm the mixture and blow across the surface to remove any excess diethylamine

-cool in an ice bath, continuing to blow and scratch until crystals form.

-vacuum filter the crude lidocain, wash the crystals with cold water and remove from the filter paper immediately.

-let dry on a watch glass, package, weigh, mp, IR & nmr spectra.

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1) Write a balanced chemical equation for the reduction of nitrobenzene with Fe in HCl to form aniline. (Fe --> FeCl3)

2) Draw the structures of at least two by-products produced in the reaction in 1).

3) Why does 2,6-dimethylaniline react with chloroacetyl chloride to produce an amide rather than a secondary amine?

4) Lidocaine is commercially sold in the form of the hydrogen chloride salt. Why?

5) In the reduction of 2,6-dimethylnitrobenzene with stannous chloride, what is the structure of the ppt that is collected by suction filtration?

6) What is the precipitate collected by filtration after the reaction with diethylamine?

7) Why do we use three moles of diethylamine for every mole of the anilide?

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Qualitative analysis

You will receive three unknown organic compounds, which you are to identify by a traditional qualitative analysis scheme. The report will consist of three forms that you will fill out and is worth 100 pts or approximately 10% of your total course grade. Read p 468-516 in your text.

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Preliminary Classification

Solubility tests: To carry out the solubility tests, approximately 0.1 g or 0.1 mL of the substance is added to 3 mL of the solvent. If most of the material appears to dissolve, the compound is considered soluble. If there is no immediate change, especially with a solid unknown, the mixture should be thoroughly stirred with a glass rod and at least 2 minutes allowed to elapse before a decision is made.

The solubility tests must be applied in the sequence given below to avoid misleading observations.

a. Solubility in water. A compound that is soluble in water must be at least somewhat polar.

b. Solubility in aqueous acid or base. A water-insoluble organic acid should dissolve in an aqueous base; an organic base that is not soluble in water should dissolve in aqueous acid. The observed solubility in each case is the result of the formation of an ionic salt which remains dissolved in the aqueous medium. It should be obvious that these tests are applied only if the original compound does not dissolve in water. If the substance is found to be soluble in 5% NaOH, indicating that it is an acid, it is tested further with 5% sodium hydrogen carbonate. Only acids stronger than carbonic acid will dissolve. A compound may therefore be classified as a strong or weak acid on the basis of these two solubility tests. An organic base can be identified by its solubility in 5% hydrochloric acid. No further classification is possible. If a compound is found to be an acid, it should also be tested with hydrochloric acid on the chance that it may contain both acidic and basic functional groups (e.g., an amino acid).

c. Solubility in sulfuric acid. A compound that is insoluble in water, hydrochloric acid, and sodium hydroxide is considered to be neutral. Those substances that contain nitrogen or sulfur are not tested further and are classed as nitrogen-sulfur neutrals (class M). Other compounds are tested for solubility in concentrated sulfuric acid. In this test, a solution in the sense of an ordinary aqueous solution is not necessarily formed. If heat is evolved, a color develops, or any other change indicative of a reaction is seen, it is concluded that the substance is "soluble" in H2SO4.

Solubility classification of some organic compounds:

S : soluble in water and soluble in diethyl etherLow MW Amines and neutral compounds

A1 (weak acids) : soluble in dilute sodium hydroxidephenols, beta-diketones.

A2 (strong acids) : soluble in dilute sodium bicarbonatecarboxylic acids, polynitrophenols, polyhalophenols, acyl halides.

B (bases) : soluble in dilute hydrochloric acid amines (except diaryl and triarylamines)

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N1 (neutrals) : soluble in conc. sulfuric acidalkenes, some arenes, ethers, water-insoluble: alcohols, aldehydes, esters, ketones.

N2 (neutrals) : insoluble in conc. sulfuric acidalkanes, halides, diarylethers.

M (nitrogen-containing neutrals)

amides, nitrocompounds, diaryl- and triarylamines, nitroarylamines.

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Indicator Classification Method:

The solubility method suffers from several shortcomings. One is that it is difficult to estimate solubility in borderline cases. There are also some instances in which a solid substance dissolves, only to react with the solvent to form an insoluble product. The indicator method overcomes these difficulties and also provides a more specific classification. That is, it is possible to classify an acid as weak, intermediate, or strong, rather than just weak or strong as in the solubility system. Bases can also be classified as weak, intermediate, or strong.

A set of four indicators, A-I, A-II, B-I, and B-II is required. To carry out the test, 1 mL of the indicator is placed in a small test tube and one drop of a liquid or about 30 mg or a solid (about as much as can be carried on the tip of a small spatula) is added to the indicator. The effect on each indicator solution is described below:

A-I Indicator (original color: purple)

If the color changes from purple to yellow, the compound is an intermediate acid (Ai) or a strong acid (As). If the color change is from purple to green, the unknown is a weak acid (Aw). To distinguish between Ai and As, you must use the A-II indicator.

A-II Indicator (original color: blue-violet)

A change from blue-violet to yellow occurs if the unknown is an intermediate acid. A strong acid causes a change from blue-violet to a shade of red.

B-I Indicator (original color: Purple)

Any base changes the color from purple to yellow.

B-II Indicator (original color: Yellow)

A weak base (Bw) has no effect (color remains yellow), while an intermediate base (Bi) produces a change from yellow to blue-violet. (There are relatively few strong organic bases. Although it is possible to detect strong organic bases by special treatment of the indicators, they will not be considered here.

Caution: The indicators are made up in nonaqueous solvents. The addition of water to any of the indicators may cause a color change. It is imperative therefore that a clean, dry test tube be used for each test, and the sample tested must be free of water.

Indicator Classification of Some Organic Compounds:

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Strong acids (As): acyl halides, some carboxylic aicds, nitrophenols.

Intermediate acids (Ai): carboxylic acids, o- and p-hydroxyaromatic aldehydes and ketones, polyhalophenols.

Weak acids (Aw): phenols, beta-diketones, some aryl esters.

Intermediate bases (Bi): aliphatic amines, heterocyclic amines.

Weak bases (Bw): primary arylamines, arylalkylamines, heterocyclic amines.

Neutrals (do not contain nitrogen): hydrocarbons, halides, alcohols, aldehydes, ketones, esters, ethers.

Neutrals (contain nitrogen): diarylamines, triarylamines, nitriles, nitrocompounds, amides, polynitroarylamines, polyhaloarylamines.

37

Chemistry 313QUALITATIVE ORGANIC ANALYSIS REPORT (33 pts)

Name Date

Unkn. No. Identity of Compound 1. Physical properties of purified material:

physical state color

b.p. m.p.

refractive index (liq. only) other

2. Preliminary Classificationa) Solubility tests (write "s" if soluble; "i" if insoluble).

H2O Et2O HCl NaOH NaHCO3 H2SO4

Classification b) Indicator tests (note the color change, if any)

A-I A-II

B-I B-II

Classification:

3. Functional Group Tests

On a separate sheet of paper, prepare a table with the column headings: Reagent, Result, and Inference. In the appropriate spaces, list the actual reagent and observed result of every functional group test applied to the unknown, and the inference drawn in each case. (See sample below.)

Reagent Result Inference 2,4-DNPH orange ppt; red color with alc.KOH carbonyl groupTollens no silver mirror or ppt ketone(no aldehyde)NH2OH, KOH no purple color no ester group

4. Probable Compounds: List all compounds with m.p. or b.p. within 5o of that of the unknown, which could be identical to the unknown. Also list the useful derivatives and their m.p.'s.

5. Derivatives made: List the derivatives of the unknown that were actually prepared and their observed m.p.'s.6. Spectroscopic Data: Tabulate ir and nmr data, if obtained.

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Name Date



b.p. m.p.





A-I A-II

B-I B-II

Classification:





5. Derivatives made: List the derivatives of the unknown that were actually prepared and their observed m.p.'s.

6. Spectroscopic Data: Tabulate ir and nmr data, if obtained.

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Name Date



b.p. m.p.





A-I A-II

B-I B-II

Classification:





5. Derivatives made: List the derivatives of the unknown that were actually prepared and their observed m.p.'s.

6. Spectroscopic Data: Tabulate ir and nmr data, if obtained.

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