Question

Write the IUPAC names of the following ketones and aldehydes wherever possible, give also common names.
\[
  A)C{H_3}CO{\left( {C{H_2}} \right)_4}C{H_3} \\
  B)C{H_3}C{H_2}CHBrC{H_2}CH\left( {C{H_3}} \right)CHO \\
  C)C{H_3}{\left( {C{H_2}} \right)_6}CHO \\
  D)Ph - CH = CH - CHO \\
 \]

Answer 1

Hint: We must know aldehydes and ketones contain the carbonyl group.

In aldehydes, the carbonyl group is attached at the end of the hydrocarbon chain. At least the carbonyl carbon is bonded to one hydrogen atom.

Aldehydes have a general formula of $R - CHO$ the general structure of an aldehyde is,

In ketones, the carbonyl group is bound to two carbon atoms.The general formula of a ketone is $RCOO$$R'$ the general structure of ketone is,

Complete step by step answer:
IUPAC nomenclature of naming ketones:

-The parent compound that is the longest carbon chain containing the carbonyl group has to be determined.
-Replace the –e ending of the parent alkane with –one suffix of the ketone family.
-The carbon atom has to be numbered. The carbonyl carbon takes the lowest possible number.

Common name nomenclature of naming ketones:
-The common names of ketones are derived by naming the alkyl groups that are bonded to the carbonyl carbon.
-The prefix used is followed by the word ketone.
-The alkyl groups are arranged alphabetically or by size.

IUPAC name and Common name of substituted aldehydes:

-The common names of substituted aldehydes are named as derivatives of straight-chain parent compounds.
-Greek letters designate the carbon atoms near the carbonyl group.
-The carbon atom bonded to the carbonyl group is alpha, the next removed is beta and so on.

-The parent compound; that is the longest continuous carbon chain containing the carbonyl group has to be determined.
-Replace the final –e of the parent alkane with –al.
-The chain beginning with the carbonyl carbon is named as carbon${\text{ - 1}}{\text{.}}$
-All the substituents are named and numbered.
-No number is used for the position of carbonyl group because it is always at the end of the parent chain. Therefore it must be carbon${\text{ - 1}}{\text{.}}$

The given compound (A) is,

The given compound is ketone since it shows the presence of double bond oxygen linked to carbon. The name of the parent carbon chain is heptane is changed into heptanone and the carbonyl group is in second position. Therefore the IUPAC name of the compound is 2-heptanone. The common name of the compound is methyl pentyl ketone since the carbonyl carbon is attached to methyl group and pentyl carbon.
The given compound (B) is,

The given compound is aldehyde since it shows the presence of $CHO$ The name of the parent carbon chain is hexane is changed into hexanal, a bromo substituent is seen in fourth position and a methyl group is seen in third position. Therefore, the IUPAC name of the compound is 4-bromo-2-methylhexanal. The common name of the aldehyde is bromo-$\beta - $methyl caproaldehyde. Caproaldehyde is the common name of hexane.
The given compound (C) is,

The given compound is aldehyde since it shows the presence of $CHO$ The name of the parent carbon chain is heptane and is changed into heptanal. Therefore, the IUPAC name of the compound is heptanal. The common name of the aldehyde is n-heptyl aldehyde.
The given compound (D) is,

The given compound is aldehyde since it shows the presence of $CHO$ the compound shows the presence of double bond, so it has –en- in its name and phenyl substitution is seen at the third position. IUPAC name of the compound is 3-phenyl prop-2-en-1-al and the common name is phenyl acrolein.

Note:
We must know that the aldehydes and ketones cannot form hydrogen bonds to one another, but they can form intermolecular hydrogen bonds with water. As result, the smaller members (five or fewer carbon atoms) are soluble in water.