Chapter 8, Problem 56P

Interpretation Introduction

Interpretation:The missing reagent required in the synthetic transformation scheme indicated should be filled sequentially.

  

Concept introduction:Grignard reagents are alkyl magnesium halides obtained from the treatment of haloalkane with magnesium in the presence of dried ether conditions. This reagent isuseful precursor for the quick synthesis of a variety of organic compounds For example, the reaction of Grignard reagent with aldehyde or ketone generates alcohol as illustrated below.

  

Methyl bromide reacts with magnesium ether to give Grignard reagent. This Grignard methyl magnesium bromide on treatment with formaldehyde gives corresponding alcohol. The mechanistic pathway for the latter reaction is as follows:

  

The polar carbonyl bond breaks and the polar Grignard reagent attack at electron-deficient carbon. Finally with the hydrolysis and work up the alcohol is formed.