Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
10.1 ORGANIC CHEMISTRYFundamentals of chemistry
INTRO TO ORGANIC
• Organic Chemistry is the field of chemistry that studies carbon-based compounds.
• Carbon has four valence electrons (can have four bonds, mostly C-H bonds)
• Carbon can undergo catenation, which is creating long chains of repeating structures (ex.
Crude oil)
• In order to understand organic chemistry you need to understand the following
concepts: chemical bonding, nomenclature, chemical structure, stoichiometric
relationships, functional groups, and reaction mechanisms
• Organic chemistry can be applied to many topics including, but not limited to,
synthetic medicines and drugs, industry and chemical kinetics.
INTRO TO ORGANIC
• The empirical formula is the simplest whole number ration of the elements present in
a compound.
• Molecular formula the total number of atoms of each element present in a molecule
of the compound. A molecular formula is the empirical formula multiplied by an
integer (the integer can be 1)
HYDROCARBONS
• Only contain carbon and hydrogen.
• Alkanes are a family of hydrocarbons.
ALKANES
• They are all straight chains and the molecular formula of all Alkanes can be found
using CnH2n+2 (non-cyclic)
• Contain only 90°angles
• Tetrahedral shape
THERE ARE DIFFERENT WAYS TO REPRESENT THE STRUCTURE
1. Write the Lewis structure to get the full structural formula
2. Write out the carbons and hydrogens as they are bonded together
3. Write the Sketch Structural Formula
4. Write the stereochemistry using dashes and wedges
Ex. Butane C4H10
#1
#2 CH3CH2CH2CH3
#3
#4
THERE ARE DIFFERENT WAYS TO REPRESENT THE STRUCTURE
#1
#2 CH3CH2CH2CH3
#3
#4
CO
PY
OR
PR
INT
TH
IS O
UT
HOMOLOGOUS SERIES
• Homologous Series are a series of compounds that have the same functional group
each member differs from the next by a common structural unit (usually –CH2–)
• Functional groups- an atom or group of atoms that give the molecules its
characteristics chemical properties. The reactive part of the molecule.
• Homologus Series have a trend physical properties like boiling point, similar
chemical properties and a similar formula
CO
PY
OR
PR
INT
TH
IS O
UT
FU
NC
TIO
NA
L G
RO
UPS
CO
PY
OR
PR
INT
TH
IS O
UT
FU
NC
TIO
NA
L G
RO
UPS
ALKENES
• All have a
C=C bond
• Follow
CnH2n (non-
cyclic)
ALCOHOLS AND AMINES
• Alchol’s mus contain –OH group. Shown below are a few examples
• Amines-there are three different amine groups in the table. These will be discussed
in more detail later in the notes.
BENZENE RINGS
• C6H6 is the molecular formula
• The molecule is planar
• Compounds with a benzene ring are called aromatic. Without a benzene ring you
can call them aliphatic.
• When something is attached to the benzene ring it will replace a hydrogen. The
formula can be written in different ways. For example C7H8 can be written as it
structural formula C6H5CH3. C6H5 is often referred to as phenyl.
BOILING POINT OF HOMOLOGOUS PAIRS
• Increasing the number of carbons will increase the boiling point for homologous
pairs.
• Changing the functional group will change the boiling points because it will change
the type of intermolecular forces
• Ranking boiling points: Alkanes (dispersion)< Esters (dipole) < Alcohols (hydrogen
bonding)
SATURATED COMPOUNDS VS. UNSTATURATED
• Saturated compounds have double or triple bonds.
• Unsaturated compounds only have single bonds
NAMING ALKANES
NAMING ALKANES (CONT)
• The following slides contain examples of each type of functional group they were
created by Lexter Supnet can be found on line at
http://www.slideshare.net/lexter1321/nomenclature-of-organic-compounds-
iupac?from_action=save
•
NOMENCLATURE
Early organic chemists often assigned names related to the origin or properties
of new compounds. Some of these names are still in common use. Citric acid if found in
citrus fruit; uric acid is present in urine; formic acid is found in ants (from the Latin word
for ant, formica); and morphine induces sleep (from Morpheus, the ancient Greek god
of sleep). As thousands upon thousands of new compounds were synthesized, it
became apparent that a system of common names was unworkable. Following several
interim systems, one recommended by the International Union of Pure and Applied
Chemistry (IUPAC) was adopted.
RULES IN NAMING ORGANIC COMP0UNDS1. Select the longest continuous carbon chain in the molecule, and use the hydrocarbon
name of this chain as the base name. Except for the common names methane, ethane,
propane, and butane, standard Greek prefixes relate the name to the number of C
atoms in the chain, as in pentane (C5), hexane (C6), heptane (C7), octane (C8),…
2. Consider every branch of the main chain to be substituent derived from another
hydrocarbon. For each of these substituents, change the ending of its name from ane to
yl. That is, the alkane substituent becomes alkyl group.
3. Number the C atoms of the continuous base chain so that the substituents appear at the
lowest number possible.
4. Name each substituent according to its chemical identity and the numbers of the C
atom to which it is attached. For identical substituents use di, tri, tetra, and so on, and
write the appropriate carbon number for each substituent.
5. Separate the numbers from one another by commas, and from letters by hyphens.
6. List the substituents alphabetically by name.
SOME COMMON ALKYL GROUPSNAME STRUCTURAL FORMULA
Methyl CH3
Ethyl CH2CH3
Propyla CH2CH2CH3
Isopropyl CH3CHCH3
Butyla CH2CH2CH2CH3
Isobutyl CH3
CH2CHCH3
s-butylb CH3CHCH2CH3
t-butylc CH3
CH3CCH3
aIn the past, the prefix normal or n- was used for a straight-
chain alkyl group, such as n-propyl or n-butylbs = secondaryCt = tertiary
ALKANE
Class
General
Structural
Formula Example
Name of
Example
Alkane R H CH3CH2CH2CH2CH2CH3 Hexane
*The functional group is shown in red, R stands for an alkyl group
ALKENE
Class
General
Structural
Formula Example
Name of
Example
Alkene C C CH2 CHCH2CH2CH3 1-Pentene
*The functional group is shown in red, R stands for an alkyl group
ALKYNE
Class
General
Structural
Formula Example
Name of
Example
Alkyne C C CH3C CCH2CH2CH2CH2CH3 2-Octyne
*The functional group is shown in red, R stands for an alkyl group
ALCOHOL
Class
General
Structural
Formula Example
Name of
Example
Alcohol R OH CH3CH2CH2CH2CH2OH 1-Butanol
*The functional group is shown in red, R stands for an alkyl group
ALKYL HALIDE
Class
General
Structural
Formula Example
Name of
Example
Alkyl halide R X** CH3CH2CH2CH2CH2CH2CH2Br 1-Bromohexane
*The functional group is shown in red, R stands for an alkyl group
**X stands for a halogen atom – F, Cl, Br, I
ETHER
Class
General
Structural
Formula Example
Name of
Example
Ether R O R CH3 O CH2CH2CH3 1-Methoxypropane
(methyl propyl ether)
*The functional group is shown in red, R stands for an alkyl group
**X stands for a halogen atom – F, Cl, Br, I
AMINE
Class
General
Structural
Formula Example
Name of
Example
Amine R NH2 CH3CH2CH2 NH2 1-Aminopropane
(propylamine)
*The functional group is shown in red, R stands for an alkyl group
**X stands for a halogen atom – F, Cl, Br, I
Exercise: Give the appropriate IUPAC name of the amine
CH3CH(NH2)CH2CH2CH3
Ans: 2-Aminopentane
ALDEHYDE
Class
General
Structural
Formula Example
Name of
Example
Aldehyde O
R C H
O
CH3CH2CH2C H
Butanal
(butyraldehyde)
*The functional group is shown in red, R stands for an alkyl group
KETONE
Class
General
Structural
Formula Example
Name of
Example
Ketone O
R C R
O
CH3CH2CH2CCH2CH3
3-Hexanone
(ethyl propyl ketone)
*The functional group is shown in red, R stands for an alkyl group
CARBOXYLIC ACID
Class
General
Structural
Formula Example
Name of
Example
Carboxylic
acid
O
R C OH
O
CH3CH2CH2C OH
Butanoic acid
(butyric acid)
*The functional group is shown in red, R stands for an alkyl group
ESTER
Class
General
Structural
Formula Example
Name of
Example
Ester O
R C OR
O
CH3CH2CH2C OCH3
Methyl butanoate
(methyl butyrate)
*The functional group is shown in red, R stands for an alkyl group
AMIDE
Class
General
Structural
Formula Example
Name of
Example
Amide O
R C NH2
O
CH3CH2CH2C NH2
Butanamide
(butyramide)
*The functional group is shown in red, R stands for an alkyl group
ARENE
Class
General
Structural
Formula Example
Name of
Example
Arene Ar H**
CH2CH3
Ethylbenzene
*The functional group is shown in red, R stands for an alkyl group
**Ar stands for aromatic (aryl) group such as the benzene ring
ARYL HALIDE
Class
General
Structural
Formula Example
Name of
Example
Aryl halide Ar X**
Br
Bromobenzene
*The functional group is shown in red, R stands for an alkyl group
**Ar stands for aromatic (aryl) group such as the benzene ring
***X stands for halogen atom – F, Cl, Br, I
PHENOL
Class
General
Structural
Formula Example
Name of
Example
Phenol Ar OH**
Cl OH
4-Chlorophenol
*The functional group is shown in red, R stands for an alkyl group
**Ar stands for aromatic (aryl) group such as the benzene ring
***X stands for halogen atom – F, Cl, Br, I
REFERENCES
• PETRUCCI, R.H., HARDWOOD, W.S., HERRING, F.G. 2002. General Chemistry:
Principles and Modern Applications. 8th Edition. Pearson Education South Asia Pte.
Ltd. Singapore.
• Collins English Dictionary – Complete & Unabridged 2012 Digital Edition
• http://science.uvu.edu/ochem/index.php