To synthesize the given compounds from butanenitrile, you can follow these steps:
A. 2-Methyl-3-hexanone:
1. Grignard Reaction: React butanenitrile (CH3CH2CH2CN) with 2 equivalents of methylmagnesium bromide (CH3MgBr) to form a tertiary alcohol.
2. Oxidation: Oxidize the tertiary alcohol to a ketone using an oxidizing agent like PCC (Pyridinium chlorochromate).
B. Pentanoic acid:
1. Hydrolysis: React butanenitrile (CH3CH2CH2CN) with H2O in the presence of a strong acid like HCl to form a carboxylic acid (butanoic acid).
2. Oxidation: Oxidize butanoic acid to pentanoic acid using an oxidizing agent like KMnO4 (potassium permanganate) or K2Cr2O7 (potassium dichromate) under acidic conditions.