A
pre-association mechanism in which one of the
molecular entities,
C, is already present in an
encounter pair with
A during formation of
B from
A, but does not assist the formation of
B, e.g.
The formation of
B from
A may itself be a
bimolecular reaction with some other
reagent. Since
C does not assist the formation of
A, it is described as being present as a spectator, and hence such a mechanism is sometimes referred to as a spectator mechanism.
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1165
InChI=1/CH4/h1H4
VNWKTOKETHGBQD-UHFFFAOYAM
InChI=1/CH5B/c1-2/h2H2,1H3
PLFLRQISROSEIJ-UHFFFAOYAG
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
doi:10.1351/goldbook.
