Which of the following pairs of compounds are positional isomers?
(a) \(CH_3 - CH_2- CH_2-\underset{O}{\underset{||}{C}}-CH_3\)
and \(CH_3 - CH_2 -\underset{O}{\underset{||}{C}}-CH_2- CH_3\)
(b) CH3 - CH2 - CH2 - CH2 - CHO
and \(CH_3 - CH_2- CH_2-\overset{O}{\overset{||}{C}}-CH_3\)
(c) \(CH_3 - CH_2- CH_2-\underset{O}{\underset{||}{C}}-CH_3\)
and \(CH_3 -\underset{CH_3}{\underset{||}{CH}}-CH_2 - CHO\)
(d) \(CH_3 - CH_2- \underset{O}{\underset{||}{C}}-CH_2 -CH_3\)
and \(^{CH_3}_{CH_3}>CH - CH_2-CHO\)
Correct answer:
(a) \(CH_3 - CH_2- CH_2-\underset{O}{\underset{||}{C}}-CH_3\)
and \(CH_3 - CH_2 -\underset{O}{\underset{||}{C}}-CH_2- CH_3\)
Explanation:
Pentan-2-one and pentan-3-one are position isomers. (b), (c), (d) contain different compounds aldehyde and ketones.