Chapter 19, Problem 19.23P

Interpretation Introduction

Interpretation:

It is to be shown how to carry out the given synthesis using a TBDMS protecting group.

Concept introduction:

To protect an alcoholic group, it is treated with $\text{TBDMS-Cl}$ to form its silyl ether derivatives like OTBDMS, which is stable under the basic condition. Ketone is reduced to its corresponding secondary alcohol by the treatment of sodium borohydride (${\text{NaBH}}_{\text{4}}$). The alcoholic group, on treatment of ${\text{PBr}}_{\text{3}}$_, is replaced by the bromine atom via ${\text{S}}_{\text{N}}\text{2}$ reaction.