Chapter 16.SE, Problem 48AP

Interpretation Introduction

a) Chlorobenzene, o-dichlorobenzene and benzene

Interpretation:

The compounds chlorobenzene, o-dichlorobenzene and benzene are to be ranked according to their reactivity towards electrophilic substitution.

Concept introduction:

Aromatic compounds that contain an ortho and para directing substituent groups (except halogens) are more reactive than benzene and that contain meta directing substituent groups are less reactive than benzene. Halogens are ortho & para directing yet deactivating groups. Hence the halogen substituted benzenes are less reactive than benzene.

To rank:

The compounds chlorobenzene, o-dichlorobenzene and benzene according to their reactivity towards electrophilic substitution.

Interpretation Introduction

b) p-bromonitrobenzene, nitrobenzene, phenol

Interpretation:

The compounds p-bromonitrobenzene, nitrobenzene and phenol are to be ranked according to their reactivity towards electrophilic substitution.

Concept introduction:

Aromatic compounds that contain an ortho and para directing substituent groups (except halogens) are more reactive than benzene and that contain meta directing substituent groups are less reactive than benzene. Halogens are ortho & para directing yet deactivating groups. Hence the halogen substituted benzenes are less reactive than benzene.

To rank:

The compounds p-bromonitrobenzene, nitrobenzene and phenol according to their reactivity towards electrophilic substitution.

Interpretation Introduction

c) Fluorobenzene, benzaldehyde, o-xylene

Interpretation:

The compounds fluorobenzene, benzaldehyde and o-xylene are to be ranked according to their reactivity towards electrophilic substitution.

Concept introduction:

Aromatic compounds that contain an ortho and para directing substituent groups (except halogens) are more reactive than benzene and that contain meta directing substituent groups are less reactive than benzene. Halogens are ortho & para directing yet deactivating groups. Hence the halogen substituted benzenes are less reactive than benzene.

To rank:

The compounds fluorobenzene, benzaldehyde and o-xylene according to their reactivity towards electrophilic substitution.

Interpretation Introduction

d) Benzonitrile, p-methylbenzonitrile, p-methoxybenzonitrile

Interpretation:

The compounds benzonitrile, p-methylbenzonitrile and p-methoxybenzonitrile are to be ranked according to their reactivity towards electrophilic substitution.

Concept introduction:

Aromatic compounds that contain an ortho and para directing substituent groups (except halogens) are more reactive than benzene and that contain meta directing substituent groups are less reactive than benzene. Halogens are ortho & para directing yet deactivating groups. Hence the halogen substituted benzenes are less reactive than benzene.

To rank:

The compounds benzonitrile, p-methylbenzonitrile and p-methoxybenzonitrile according to their reactivity towards electrophilic substitution.