Chapter 4, Problem 57PP

Interpretation Introduction

Interpretation:

Chair conformations of glucose should be drawn and most stable conformer is needed to be predicted between them.

Concept introduction:

Chair conformer: chair conformer is a stable conformer for cyclohexane compound. In this chair conformer two positions are important for substitutions one is equatorial and other one axial position. Axial positions are parallel to the axis of ring while equatorial positions are perpendicular to the axis of the ring.

Example:

After ring flip of the conformer, axial position becomes equatorial and equatorial position becomes axial.

Stereochemistry conversions in chair conformation are shown below.

Substituent position	cis	trans
1,2 position	(a,e) or (e,a)	(a,a) or (e,e)
1,3 position	(a,a) or (e,e)	(a,e) or (e,a)
1,4 position	(a,e) or (e,a)	(a,a) or (e,e)

To find: chair conformers of glucose molecule and stable one between conformers.

Given compound is glucose.