Diethyl propanedioate is treated with one equivalent of NaOEt and one equivalent of CH3I, then again with one equivalent of NaOEt and one equivalent of CH3CH2Br. Heating with aqueous acid then gives which acid?

JEE Advanced levelSingle correct optionDifficulty 3 of 3co202

Diethyl propanedioate is treated with one equivalent of $NaOEt$ and one equivalent of $CH X_{3} I$ , then again with one equivalent of $NaOEt$ and one equivalent of $CH X_{3} CH X_{2} Br$ . Heating with aqueous acid then gives which acid?

The two successive alkylations give diethyl 2-ethyl-2-methylpropanedioate. Hydrolysis gives the diacid, and decarboxylation removes one

COOH

, leaving

CH X_{3} CH X_{2} CH (CH X_{3}) COOH

, 2-methylbutanoic acid.