Chapter 20, Problem 73P

Interpretation Introduction

Interpretation:

The explanation corresponding to the given statement that $80\%$ of $\text{D}-\text{idose}$ exists in the anhydrous form in an aqueous solution at $\text{100}\text{°C}$, but only $0.1\%$ of $\text{D}-\text{idose}$ exists in the anhydro form under the same condition has to be given.

Concept Introduction:

The chair conformers are stable forms of cyclic compounds.  In chair conformation, substituent’s prefers to place at equatorial positions.  This is due to unwanted interactions between those substituent’s that are placed at axial positions.  These interactions cause repulsion and that leads to the un-stability in molecule.  The general interactions that occur between axial substituents are $1,3-$ diaxial interactions.