Functional Groups
– Alkenes
• Ethene (ethylene) is a major industrial feedstock
– Used in the production of ethanol, ethylene oxide and the
polymer polyethylene
• Propene (propylene) is also very important in industry
– Molecular formula C3H6
– Used to make the polymer polypropylene and is the starting
material for acetone
• Many alkenes occur naturally
2
– Alkynes
• Ethyne (acetylene) is used in welding torches
because it burns at high temperature
• Many alkynes are of biological interest
– Capillin is an antifungal agent found naturally
– Dactylyne is a marine natural product
– Ethinyl estradiol is a synthetic estrogen used in oral
contraceptives
– Benzene: A Representative Hydrocarbon
• Benzene is the prototypical aromatic compound
– The Kekulé structure (named after August Kekulé who formulated it)
is a six-membered ring with alternating double and single bonds
• Benzene does not actually have discreet single and double
carbon-carbon bonds
– All carbon-carbon bonds are exactly equal in length (1.38 Å)
– This is between the length of a carbon-carbon single bond and a
carbon-carbon double bond
• Resonance theory explains this by suggesting there are two
resonance hybrids that contribute equally to the real structure
– The real structure is often depicted as a hexagon with a circle in the
middle
Some Well-known Aromatic Compounds
CO 2H O
OCCH3
acetyl salicylic acid
ibuprofin
HO2C
HO 2C CH3
N O
CH2CNH S
N
CH3
NH penicillin G CO H
N 2
lysergic acid
OH
O
morphine
OH
- Alkyl Halides
In alkyl halides, a halogen (F, Cl, Br, I)
replaces the hydrogen of an alkane
– Alcohols
• In alcohols the hydrogen of the alkane is replaced
by the hydroxyl (-OH) group
– An alcohol can be viewed as either a hydroxyl derivative
of an alkane or an alkyl derivative of water
• Alcohols are also classified according to the carbon
the hydroxyl is directly attached to
Chapter 2
Some Alcohols
OH OH
CH3CH2OH HO CHCH2NH2 CHCHNHCH3
CH3
ethanol HO adrenaline pseudephidrine
OH
HOCH2CHCH 2OH
glycerol cholesterol
HO
Alcohols are Found in Many Natural Products
HO
O N CH3
H
HO
Morphine
most abundant of opium's alk aloids
CH3 CH3
N N Designer Drugs
OH OH
O O
OH OCH3
morphine codeine
CH3 CH3
N N
O OAc
O O
OCH3 OAc
oxycodone heroin
oxycontin (slow release)
percocet (w/ acetominophen)
– Ethers
• Ethers have the general formula R-O-R or R-O-R’
where R’ is different from R
– These can be considered organic derivatives of water in
which both hydrogens are replaced by organic groups
– The bond angle at oxygen is close to the tetrahedral
angle
– Amines
• Amines are organic derivatives of ammonia
– They are classified according to how many alkyl groups
replace the hydrogens of ammonia
– This is a different classification scheme than that used in
alcohols
– Aldehydes and Ketones
• Both contain the carbonyl group
• Aldehydes have one carbon attached to the carbonyl group
• Ketones have two organic groups attached to the carbonyl
group
• The carbonyl carbon is sp2 hybridized
– It is trigonal planar and has bond angle about 120o
Adrogenic/Anabolic Steroids
CH3 OH CH3 O
CH3 H CH3 H
H H H H
O O
Testosterone Androstenedione
– Carboxylic Acids, Esters and Amides
• All these groups contain a carbonyl group bonded
to an oxygen or nitrogen
• Carboxylic Acids
– Contain the carboxyl (carbonyl + hydroxyl) group
• Esters
– A carbonyl group is bonded to an alkoxyl (OR’) group
Analgesics
CO2H O
OCCH3
(S)(+)-
acetyl salicylic acid ibuprofin
HO2C
Fats and Fatty Acids
CO2H
palmitic acid (a fatty acid)
O
CH2 OCR
O
CH OCR
O
CH2 OCR R = n-C15H31
a triglyceride
From Ergot Fungus
HO 2C CH3
N
H
(+) lysergic acid
NH
Functional Groups
link to Carey’s site
(CH3)2N
O O
OH
H2NCHCNHCHCOCH 3
C CH
HOCCH 2 CH2
O
O
Mifepristone (RU-486) Aspartame
• Amide
– A carbonyl group is bonded to a nitrogen derived from
ammonia or an amine
– Nitriles
• An alkyl group is attached to a carbon triply bonded
to a nitrogen
– This functional group is called a cyano group
Chapter 2
Summary of Important Families of Organic
Compounds
Summary (cont.)
From the Bark of the
Pacific Yew Tree
O
O O OH
O NH O
O
O
OH O O
OH
O
O
Taxus brevifolia