Download Introduction to Organic Compounds

X. ORGANIC COMPOUNDS
A. Covalent Bonding With Carbon
1. Number of Bonds
a. Carbon always forms 4 covalent bonds since it has 4 unpaired electrons.
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C
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C
C
C
b. Hydrogen always forms 1 covalent bond, one unpaired electron.
H
c. Oxygen always forms 2 covalent bonds, 2 unpaired.
O
O
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d. Nitrogen always forms 3 covalent bonds, 3 unpaired. (We will only see single
bonds.)
N
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2. Carbon is unique since it can bond with itself to form long continuous chains, or
branched chains. This is why life is based on carbon, there is no limit to the number
of compounds.
If there are no O or N atoms, the 4 bond requirement is fulfilled by H atoms.
Example(1) Fill in the H atoms in the molecules below:
CCCC
CCCCC
CCCCC
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C
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C
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Example(2) Fill in the H atoms in the molecules below:
COC
CCCO
CCNC
CCCN
CCCC
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O
3. Condensed Structural Formulas
Example(1) Give the condensed structural formulas of the molecules below:
H H H H
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H  CCCC H
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H H
H
H H
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H CCCCCH
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H
H H
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H H H H H
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H CCCCC
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H H | H H
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H C
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H
Example(2) Give the condensed structural formulas of the molecules below:
COC
CCCO
CCCN
ANSWERS:
CH3OCH3
CH3CH2CH2NH2
CCNC
CCCC
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O
CH3CH2CH2OH
CH3CH2NCH3
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H
CH3CCH2CH3
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O
Example(3) Give the condensed structural formulas of the molecules below:
CCCC
NCC C
CCCCC
OCC
CCCCC
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C
OCCC
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O
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4. Hydrocarbons – contain only carbon and hydrogen
a. Alkanes – Only single bonds between carbons. e.g. CCCC
b. Alkenes – One or more double bonds between 2 carbons. e.g. CCCC
c. Alkynes – One or more triple bonds between 2 carbons. e.g. CCCCC
B. Alkanes
1. General formula: CnH2n+2
H H H H H H
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HCCCCCCH
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H H H H H H
each C has 2 H’s, and then an extra H on the left
and right end carbons
2. Naming “straight chained” alkanes”: root name +ane
CH4
C–C
C–C–C
C–C–C–C
methane
ethane
propane
butane
pentane
hexane
heptane
octane
nonane
decane
3. Branched Alkanes and Isomers
a. Isomers: different molecules that by coincidence have the same chemical formula.
Example(1) Draw two different molecules with the formula C4H10
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Example(2) Draw three different molecules with the formula C5H12
Note that there is no such thing as a branch on an end carbon.
b. Naming Branched Alkane
example(1): Name following compounds:
C
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CCCC
CCCC
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C
example(2): Name following compounds:
C
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CCCC
C
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CCC
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C
example(3): Name following compounds:
CCCCCC
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C C
CCCCC
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C
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C
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C. Alkenes
1. General formula of alkenes: CnH2n
e.g.
H H H H
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HCCCCH
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H
H
2. Unsaturated: carbons are not completely filled or saturated with hydrogen.
Anytime there is one or more double bonds between carbons, one or more triple
bonds between carbons, the compound is unsaturated.
. 3. Hydrogenation: The addition of hydrogen to an unsaturated compound.
(done at high pressure and with a catalyst.)
Alkene + H2  Alkane
example(1): What product is produced when CH3CHCHCH3 is hydrogenated?
example(2): What product is produced when CH2CHCH3 is hydrogenated?
4. Isomers
example(1): Which molecule or molecules are isomers of: CCCC
CCCC
CCCC
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C
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CCC
5. Naming Alkenes
example(1): Name following unbranched alkenes:
CCCC
CCCC
D. Alkynes
1. General formula of alkynes: CnH2n-2
e.g.
H
H
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HCCCCH
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H
H
example(1): If an alkyne has 6 carbon atom, how many hydrogen atoms will it have?
2. Unsaturated: carbons are not completely filled or saturated with hydrogen.
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3. Hydrogenation: The addition of hydrogen to an unsaturated compound.
(done at high pressure and with a catalyst.)
Alkyne + 2H2  Alkane
example(2): What product is produced when CH3C≡CCH3 is hydrogenated?
4. Isomers
example(3): Draw the unbranched isomers of C5H8
5. Naming Alkynes
Example(4): Name following compounds:
CCCC
CCC≡C
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E. Ring Structures
Many organic compounds and biochemical compounds have “rings” in them. They are almost
always represented in a way that we have not seen up to now.
H2
C
H2C
CH2
H2C
CH2
Carbons with Bonds and Hydrogen
C
H2
C
C
C
C
C
Carbons with Bonds Only
C
With Carbon Bonds Only
With Alternating Bonds Between the Carbons
Called Aromatic
Another way to represent what is above
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JUST FOR FUN – WHAT IS THE DIFFERENCE BETWEEN BOYS AND GIRLS?
JUST A FEW ATOMS!!!!
GIRLS
BOYS
E. Oxygen Functional Groups
A functional group is a special group of atoms other than singly bond carbons and hydrogens
Oxygen always forms 2 bonds: O or O=
1. Alcohols – contain one O atom singly bonded to one carbon.
example(1): Add the H atoms to the molecules below
CCCO
CCC
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O
Any hydrocarbon with a covalently bonded OH is no longer a hydrocarbon, but an
alcohol.
A covalently bonded OH is called a hydroxyl group. (An ionicly bonded OH-1 is a
hydroxide.)
a) General structure
hydrocarbonOH
hydrocarbon is abbreviated as R
ROH
b) Naming Alcohols
IUPAC: root + anol
COH
IUPAC
Common System Name
methanol
methyl alcohol (poisonous)
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CCOH
ethanol
CCCOH
1-propanol
CCC
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O
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H
2-propanol
CCC
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O
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H
ethyl alcohol (drinkable but poisonous
in large quantities)
isopropyl alcohol (rubbing alcohol)
CCCC
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O
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H
2. Ethers – contain one O atom singly bonded between two carbon groups.
CCOC
a) General structure
CCCOCC
hydrocarbonOhydrocarbon
ROR
b) Naming
Common System: name the R groups as branches off of the ether function.
CCOC
CCCOCC
CCOCC
ethyl methyl ether
ethyl propyl ether
(or propyl ethyl ether is OK)
diethyl ether (common ether)
3. Aldehydes – contain one O atom doubly bonded on an end carbon.
O
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CCCCC
O
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CCCC
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CCCC
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C=O
a) General structure
O
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hydrocarbonCH
O
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RCH
b) Naming Aldehydes DO NOT HAVE TO DO
c) Common Aldehydes
formaldehyde R = H
acetaldehyde R = CH3
form is an old name for 1 carbon
acet is an old name for 2 carbon
4. Ketones – contain one O atom doubly bonded on any carbon except an end carbon.
O
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CCCCC
a) General structure
O
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CCCC
CCCCC
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O
O
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hydrocarbonChydrocarbon
O
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RCR
b) Naming Ketones - Common System: name the R groups as branches off of the ketone
function.
O
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CCCCC
methyl propyl ketone
(OR propyl methyl ketone
is OK)
O
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CCCC
ethyl methyl ketone
(OR methyl ethyl ketone
is OK)
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CCC
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O
dimethyl ketone –commonly
called acetone (acet – 2 C’s)
5. Organic Acids (Carboxcylic Acids)
a) General structure
O
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hydrocarbonCOH
O
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RC OH
b) Naming Carboxcylic Acids DO NOT HAVE TO DO
c) Common Carboxcylic Acids
form is an old name for 1 carbon
acet is an old name for 2 carbon
O
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HCOH
O
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CH3C OH
6. Esters
a) General structure
O
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hydrocarbonC—Ohydrocarbon
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O
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RC OR
JUST FOR FUN
Octyl acetate
Orange
s
Isoamyl acetate
Banana
Ethyl Butyrate
Pineapple
Butyl acetate
Apple
Methyl trans-cinnamate
Strawberry
F. Nitrogen Functional Groups
1) Amines R—N—H
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H
R—N—R
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H
R—N—R
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R
a) Naming Amines – The R groups are name like branches off of the nitrogen,
followed by the ending amine. (No space between the names of
the branches.)
- 75 Name the following amines
C—C—N—H
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H
C—N—H
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C
C—N—C—C—C
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C
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C
JUST FOR FUN
Amphetamine
2) Amides
—C—N—
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O
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