Answer ( 1 )

  1. Draw the structure of the neutral product formed in the following reaction of dimethyl malonate and methyl vinyl ketone.

    Conjugated attack by a nucleophile is called as 1,4-attack or Micheal attack. This type of attack is done by a soft nucleophilic site. For example, Gilman reagent attacks the vinyl ketones in this way.

    Solution and Explanation:
    The alpha hydrogen atoms of the dimethyl malonate are very acidic because after deprotonation of that hydrogen the conjugate base is stabilized by two adjacent carbonyl groups.

    In this reaction, methanolate acts as a base and deprotonate the acidic alpha hydrogen atom of the dimethyl malonate and form an enolate. The enolate act as a nucleophile and 1,4-attack takes place to the methyl vinyl ketone. After protonation, the final product is formed.

    The structure of the final product is shown below.

    Best answer

Leave an answer