Chapter 20, Problem 83IP

Interpretation Introduction

Interpretation: The three step mechanism for the given conversion has to be proposed.

Concept Introduction:

 For any given transformation, the following mandatory observations have to be made clear to predict the synthetic scheme:

• Observe whether there is any change in the carbon skeleton.
• Observe whether there is any change in the location of the functional group.
• Predict the synthetic scheme in such a way that these two observations have to be achieved within the minimum chemo selective steps.

The given synthetic conversion is:

The following reactions are predicted to take place in the conversion:

Williamson Ether synthesis:

In the given conversion, the alcoholic group has been converted into ether using the method of Williamson Ether synthesis. It is the synthesis of ether using an organo halide $\left(\text{RX}\right)$ reagent and a base.

Reduction with $LiAl{H}_4$ - Lithium aluminium hydride

It is a reducing agent. It reduces aldehydes, ketones and carboxylic acids into alcohols. In the given conversion, the ester group has been reduced into alcohol.

Addition of Acid chloride to alcohol:

In the given conversion this method is used to convert the obtained alcohol into ester, which is being an alternative way for Fischer esterification. Fischer esterification is not preferred because acidic condition is involved in it which may cause undesired side chain reactions with the other functional groups present. In this addition reaction, the obtained alcohol has been added with the desired acid chloride to obtain the desired ester functional group.