Question

Which of the following is added to the tetrahedral intermediate when it reacts with a proton from the reaction medium?

(a) Nu^–

(b) H^+

(c) Both Nu^– and H^+

(d) OH^–

The question was asked during an internship interview.

My question is from Aldehydes and Ketones Chemical Reactions in division Aldehydes, Ketones and Carboxylic Acids of Chemistry – Class 12

Answer 1

Right choice is (b) H^+

The explanation is: A H+ proton is added to the negative O atom of the alkoxide intermediate to form an electrically neutral addition product. The Nu^– is added in the first step itself when it attacks the electrophilic carbon centre in a slow step.