Chapter 10, Problem 10.24P

Interpretation Introduction

(a)

Interpretation:

The complete mechanism for the given reaction is to be drawn, and the major product is to be predicted.

Concept introduction:

Under neutral conditions, a nucleophile attacks an epoxide at the less highly alkyl-substituted C atom of the ring, from the side opposite the O atom. Strong nucleophiles favor ${\text{S}}_{\text{N}}\text{2}$ reactions; the ${\text{S}}_{\text{N}}\text{2}$ reaction proceeds faster at carbon with less steric hindrance, followed by proton transfer. The strong nucleophile attacks from backside, and the substituents that remain are bonded to the carbon atom.

Interpretation Introduction

(b)

Interpretation:

The complete mechanism for the given reaction is to be drawn, and the major product is to be predicted.

Concept introduction:

Under neutral conditions, a nucleophile attacks an epoxide at the less highly alkyl-substituted C atom of the ring, from the side opposite the O atom. Strong nucleophiles favor ${\text{S}}_{\text{N}}\text{2}$ reactions; the ${\text{S}}_{\text{N}}\text{2}$ reaction proceeds faster at carbon with less steric hindrance, followed by proton transfer. The strong nucleophile attacks from backside, and the substituents that remain are bonded to the carbon atom.