Chapter 10, Problem 10.52P

Interpretation Introduction

Interpretation:

For each of the given reactions, the complete, detailed mechanism is to be drawn, and the major product is to be given.

Concept introduction:

Epoxides react readily under neutral and basic reaction conditions. The mechanism for the epoxides under these conditions consists of an ${\text{S}}_{\text{N}}\text{2}$ step followed by a proton transfer reaction. Thus, epoxides can undergo ${\text{S}}_{\text{N}}\text{2}$ reactions in neutral or basic reaction conditions so as to relieve the ring strain, and this compensates for the poor leaving group ability of alkoxides (${\text{RO}}^{-}$). Under neutral or basic conditions, a nucleophile attacks an epoxide at the less substituted (less sterically hindered) carbon atom of the ring, from the side opposite the oxygen atom.

Under acidic conditions, a nucleophile attacks an epoxide at the more substituted carbon atom.