A quantitative representation of
selectivity in
aromaticsubstitution reactions
(usually
electrophilic, for monosubstituted benzene derivatives). If the
partial rate factor,
, expresses the reactivity of a specified position in the aromatic compound
PhX
relative to that of a single position in benzene, then the
selectivity factor
(expressing discrimination between
p- and
m-positions in
PhX) is defined as:
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1162
