The
attachment of an
entering group to a position in an aromatic compound already carrying a
substituent group (other than hydrogen). The
entering group may displace that substituent group but may also itself be expelled or migrate to
a different position in a subsequent step. The term '
ipso-substitution' is not used, since it is synonymous with substitution. For example:
where E + is an
electrophile and Z is a substituent (other than hydrogen).
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1128
