Chapter 19, Problem 84P

(a)

Interpretation Introduction

Interpretation: The method of preparation of biphenyl from benzene as one of the starting material should be determined

Concept introduction:

Halogenation (chlorination) process performing on benzene in the presence of anhydrous $AlC{l}_{3}orFeC{l}_3$ gives chlorobenzene in good yield.

The reaction can be represented as follows,

Fittig reaction

Aryl halides give anomalous compounds when treated with sodium in dry ether, in which two aryl groups are joined together.

(b)

Interpretation Introduction

Interpretation: The method of preparation of benzophenone from benzene as one of the starting material should be determined

Concept Introduction:

Friedel-Crafts acylation:

This reaction involves the attachment of an acyl group to an aromatic ring; an H atom attached to an aromatic ring is replaced by a Carbon atom where C is part of $\text{C=O}$.

The role of anhydrous aluminum chloride is to generate a stable carbocation complex.

Acylation of benzene can be represented as follows,

$C_6{H}_6+RCOCl\to C_6{H}_{5}COR+HCl$