Organic Chemistry

604 CHAPTER 15 Aromaticity • Reactions of Benzene

15.7 Nomenclature of Monosubstituted Benzenes

Some monosubstituted benzenes are named simply by stating the name of the sub-

stituent, followed by the word “benzene.”

Some monosubstituted benzenes have names that incorporate the name of the sub-

stituent. Unfortunately, such names have to be memorized.

With the exception of toluene, benzene rings with an alkyl substituent are named as

alkyl-substituted benzenes or as phenyl-substituted alkanes.

When a benzene ring is a substituent, it is called a phenyl group. A benzene ring with

a methylene group is called a benzyl group. The phenyl group gets its name from

“pheno,”the name that was rejected for benzene (Section 15.0).

chloromethylbenzene

benzyl chloride

CH 2 Cl

a phenyl group a benzyl group

CH 2

O

diphenyl ether dibenzyl ether

CH 2 OCH 2

toluene phenol aniline benzenesulfonic acid

CH 3 OH NH 2 SO 3 H

bromobenzene chlorobenzene nitrobenzene

used as a solvent

in shoe polish

ethylbenzene

Br Cl NO 2 CH 2 CH 3

OH

O

C

anisole benzaldehyde

H

O

styrene benzoic acid benzonitrile

OCH 3 CH CH 2 C CN

isopropylbenzene

cumene

CH 3 CHCH 3

sec-butylbenzene

CH 3 CHCH 2 CH 3 CH 3 CHCH 2 CH 2 CH 3 CH 3 CH 2 CHCH 2 CH 3

tert-butylbenzene

CH 3 CCH 3

CH 3

2-phenylpentane 3-phenylpentane