Chapter 20, Problem 47P

Interpretation Introduction

Interpretation:

The mechanism for interconversion of $\alpha$-D-glucose and $\beta$-D-glucose in dilute $\text{HCl}$ is to be drawn.

Concept Introduction:

The hydroxyl group of anomeric carbon in $\alpha$-D-glucose is protonated by an acid. The lone pair on the ring helps in eliminating a molecule of water which results in the formation of oxocarbenium ion. It is planar molecule. When water approaches from the top of the plane, $\beta$-D-glucose is formed.