Question

Draw the mechanism for the addition of methylmagnesium bromide to propanoyl chloride (CH3CH2COCl) to give 2-methyl-2-butanol.

Answer 1

Answer:

Reaction mechanism has been given below

Explanation:

• Propanoyl chloride contains an electrophilic carbonyl center to give  nucleophilic acyl substitution reaction by removing Cl group with a strong nucleophile like methylmagnesium bromide.
• Two equivalent of methyl magnesium bromide react with cabonyl center followed by protonation of negatively charged oxygen atom gives 2-methyl-2-butanol.
• In the first step, nucleophilic acyl substituion occurs. In the second step, nucleophilic addition occurs. In the third step, protonation occurs.
• Reaction mechanism has been shown below.