1.4 Functional Groups with C = O Bond
C=O is called a carbonyl group
Aldehydes
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organic compounds with the carbonyl group(C=O) on the end of a chain
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general formula
Example
Ketone
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organic compound that has a double bonded oxygen on any carbon within the carbon chain
General formula
Example
Naming aldehydes
1. Name the parent alkane. label carbons from side closest to the functional group
2. Replace –e with –al. No need to give a position number for the carbonyl group because it will
always be on carbon 1
Naming Ketones
1.
2.
3.
4.
Name the parent alkane main chain must contain the C=O group
If only one ketone group replace –e with –one.
if more than one ketone group keep the –e suffix and a suffix such as –dione or –trione
Position numbers are needed for carbon chains more than 4 carbons long. # carbon chain so
that the functional group is on the lowest possible Carbon
Physical properties of aldehydes and ketones
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C=O is polar so aldehydes and ketones are polar
Shorter the chain more soluble and more polar. Less soluble if longer and less polar
boiling points of aldehydes and ketones are lower than corresponding alcohols and higher than
corresponding alkanes
Additional Characteristics of aldehydes and ketones
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strong pungent smell for aldehydes, ketones sweet smell
longer the aldehyde more pleasant smelling ex cinnamaldehyde
often in perfumes
since they are polar can act as polar solvents, because of the non-polar hydrocarbon side they
can also act as non-polar solvent (Demo)
Carboxylic acids

organic compound with a Carboxyl group (COOH
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General formula
examples
Naming a carboxylic acid
1. Name the parent alkane
2. replace the –e with –oic acid
3. Label the chain from side closest to the functional group. carboxyl group is always on Carbon 1
in a carboxylic acid
Physical Properties of Carboxylic acid
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Polar
Smaller chains are more soluble and solubility decreases as chain size increases.
melting points and boiling points are very high
Additional Characteristics
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often unpleasant odours
the –OH group does not behave like the basic Hydroxide ion (OH-)
Carboxylic derivatives
Ester
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General formula
Naming Esters (Names are made in 2 parts)
1. Identify the main part of the ester which contains the C=O group. Name the parent acid
2. Replace –oic acid with –oate
3. The second part of the name is the alkyl group that is attached to the -O atom.
4. put names together
Physical Properties
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usually polar
small esters soluble
low boiling points and volatile at room temp
Additional Characteristics
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pleasant odours and tastes, perfumes and artificial flavours
Amides
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Combination of a carboxylic acid and ammonia or an amine
carbon atom double bonded to an oxygen and single bonded to a nitrogen
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general formula
Examples
Naming an amide
1. Name the parent carboxylic acid (side that contains C=O) C=O side always position 1
2. replace –oic acid with suffix –amide
3. Decide if
a. primary
i. If there are 2 Hydrogen atoms and no alkyl groups attached to the Nitrogen.
ii. No prefixes
iii.
b. secondary
i. if there is one alkyl group attached to the nitrogen (N)
ii. name the alkyl group and give it location letter N to indicate that it is bonded to
the Nitrogen
iii.
c. tertiary
i. if there are 2 alkyl groups
ii. place alkyl groups in alphabetical order
iii. use location Letter N- before each group to indicate it is bonded to Nitrogen
iv. if groups are identical use N,N-
v.
4. Put name together: Prefix + Root + Suffix.
Physical Properties of Amides
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similar to carboxylic acids
soluble in water decreases with size
Primary amides much higher melting points and boiling points than carboxylic acids
many simple amides are solids at room temp
Additional Characteristics
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acetaminophen pain killer
Urea in urine of many mammals used as fertilizer.