Question

Two isomeric ketones, 3-pentanone and 2-pentanone can be distinguished by:

• A. $NaS{O}_{3}H$
• B. $NaCN/HCl$
• C. 2,4-DNP
• D. $I_2/NaOH$

Answer 1

Answer: (A), (D)

Two isomeric ketones, 3-pentanone $C{H}_{3}C{H}_{2}COC{H}_{2}C{H}_3$ and 2-pentanone $C{H}_{3}COC{H}_{2}C{H}_{2}C{H}_3$ can be distinguished by $I_2/NaOH$. The name of the reaction is iodoform reaction and is given by compounds containing methyl keto group $C{H}_{3}CO$
We can also use $NaS{O}_{3}H$ to distinguish 3-pentanone and 2-pentanone.