MDCAT Chemistry MCQ #380

During the synthesis of a cyanohydrin from propanone, the addition of HCN is catalyzed by a base. What is the specific role of the base?

MDCAT Chemistry MCQ #380

  1. Question 1

    Q1. During the synthesis of a cyanohydrin from propanone, the addition of HCN is catalyzed by a base. What is the specific role of the base?

    • A) HCN is already a strong nucleophile and reacts directly
    • B) OH- ions protonate the carbonyl oxygen to increase reactivity
    • C) The catalyst increases the electrophilicity of the carbonyl carbon
    • D) OH- ions react with HCN to generate the stronger CN- nucleophile

    Answer: OH- ions react with HCN to generate the stronger CN- nucleophile

    Explanation: Hydroxide ions generate CN- ions from HCN, which act as the nucleophile. Option A is wrong because HCN is a weak acid.