FUNCTIONAL GROUPS NOTE
Alcohols
• Organic compounds containing a hydroxyl group -OH
• E.g. ethanol, cholesterol, retinol (vitamin A)
Naming:
• -ol suffix e.g. methane + OH = methanol
Polyalcohols
• Alcohols containing more than one -OH
group
• -diol, -triol suffix
• Or hydroxy prefix
1,2-dihydroxyethane
1,2,3-trihydroxypropane
Properties of Alcohols
• More polar and can hydrogen bond
– Higher boiling points
– More soluble in polar solvents
• Long-chain alcohols are nonpolar (hydrocarbon portion) and polar (-OH)
– Ideal solvents in organic reactions because
they will dissolve both polar and nonpolar compounds
Hydration Reactions
• Alkene + water --> alcohol
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Combustion of Alcohols
Elimination Reactions
Dehydration (Condensation) Reactions:
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Under certain conditions alcohols can decompose to produce alkenes and water
A catalyst (sulfuric acid) removes a hydrogen atom and a hydroxyl group from neighbouring
carbons
Resulting in C=C and H2O
Ethers
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Molecules with C-O-C group
More polar than hydrocarbons
But, unlike alcohols, ethers cannot hydrogen bond
Naming:
• Add oxy to the prefix of the smaller hydrocarbon group and
join it to the alkane name of the larger hydrocarbon group
• E.g. CH3-O-C2H5 is methoxyethane
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Condensation Reactions
• When two alcohols combine, an ether and water are formed
Aldehydes and Ketones
Ketone: Molecule with a carbonyl group (C=O) between two carbon atoms. Alkane name with -one
suffix
Aldehyde: Molecule with a carbonyl group (C=O) on a terminal carbon. Alkane name
with -al suffix
Properties of Aldehydes and Ketones
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Lower boiling point and less soluble in water than alcohols (no -OH)
More polar than hydrocarbons (higher boiling points and more soluble)
Good solvents (both polar and nonpolar)
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Oxidation Reactions
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Alcohol + an oxidizing agent (removes electrons) to form an aldehyde or ketone and water
The oxidizing agent removes two H-atoms (one from the -OH group and one from the
adjacent carbon) resulting in C=O and H2O
Hydrogenation Reactions
• The C=O double bond can undergo an addition reaction with hydrogen to form an -OH group.
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Aldehydes always produce 1° alcohols
• Ketones always produce 2° alcohols
Carboxylic Acids
• Molecules with a carboxyl group –COOH
• E.g. lactic acid, citric acid
Alkane name with -oic acid
E.g. methanoic acid
Properties of Carboxylic Acids
 Polar and can hydrogen bond
 Similar properties to alcohols (smaller members are soluble in water, larger
members are insoluble)
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pH < 7 (H-atom in -OH group)
Oxidation Reactions
Recall: A 1° alcohol can be oxidized to form an aldehyde.
An aldehyde can be further oxidized to form a carboxylic acid
A ketone cannot be oxidized because there is no free H-atom
Esterfication
Recall: acid + base --> salt + water (neutralization reaction)
Carboxylic acid + alcohol --> ester + water
Properties of Esters
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• Similar to carboxylic acids, but lacking -OH group
• Esters are less polar (less soluble in water), lower boiling
points (no H-bonds)
Not acidic
Naming Esters
• 1st part is the name of the alkyl group in the alcohol
• 2nd part is the ending of the acid name changed from -oic
to –oate
Amines
• An ammonia molecule in which one or more H-atoms are substituted by alkyl or
aromatic groups
Naming:
• Amino + alkane name OR
• Alkyl group + amine
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Naming 2° and 3° Amines
• N- prefix used for the substituted groups on the nitrogen atom
• Alkyl groups are listed alphabetically
Properties of Amines
• N-C, and N-H polar bonds
• H-bonding occurs but N-H is less polar than O-H
Synthesizing Amines from Alkyl Halides
Alkyl halide + ammonia --> 1° amine + HX
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Alkyl halide + 1° amine --> 2° amine + HX
Alkyl halide + 2° amine --> 3° amine + HX
Amides
• Similar to esters, except N instead of O
Naming Amides
• 1st part is the name is from the amine
• 2nd part is the ending of the acid name changed from –oic to -amide
• Alphabetical order with N- groups
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N-ethyl propanamide
Carboxylic acids + ammonia/1°/2° amines--> amides + water
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