Identify the product A in the following reaction:

Step-by-step solution

The given reactant is diethyl carbonate, C ₂ H ₅ O - C (= O )- OC ₂ H ₅ . When diethyl carbonate reacts with Grignard reagents, it undergoes successive nucleophilic acyl substitution reactions. The first equivalent of methylmagnesium bromide ( CH ₃ MgBr ) attacks the electrophilic carbonyl carbon of diethyl carbonate. The tetrahedral intermediate collapses by expelling an ethoxide ion ( C ₂ H ₅ O ^- ), resulting in the formation of an ester (ethyl acetate). C ₂ H ₅ O - C (= O )- OC ₂ H ₅ + CH ₃ MgBr CH ₃- C (= O )-