Chapter 6, Problem 40P

Interpretation Introduction

Interpretation:

A reasonable series of synthetic transformations for converting $\text{trans-2-methylcyclopentanol}$ and $\text{1-methylcyclopentanol}$ to $\text{cis-2-methylcyclopentyl acetate}$ is to be suggested.

Concept Introduction:

Alkyl sulfonates are prepared by the reaction of an alcohol with methyl sulfonyl chlorides. These reactions are carried out in suitable solvents such as trimethylamine, amines, etc...

In these reactions, the hydrogen atom of the hydroxyl group in alcohols is substituted by the methyl sulfonate group.

Their preparation involves the oxygen of the alcohol and not the carbon to which the oxygen is attached.

The stereochemistry of the original alcohol and the carbon skeleton both are maintained when the alcohols are converted to their corresponding alkyl sulfonates.

If the structure for the product molecule is known, then the corresponding reactant alcohol can be found out by replacing the methyl sulfonate group by the hydrogen atom without changing the stereochemistry of the alcohol molecule.

The reaction of this methane sulfonate with sodium acetate in acetic acid produces the corresponding alkyl acetate and this reaction follows the ${\text{S}}_{\text{N}}2$ mechanism pathway with the inversion of configuration at the chirality center.

Alcohols are converted to corresponding alkenes in presence of strong acids such as sulfuric acid at around ${\text{200}}^0$ C. More substituted alkene is the major product.

Alkenes are converted into alcohols using hydroboration-oxidation. This reaction produces less substituted alcohol as a major product.