The situation in which reaction parameters that characterize different bond forming
or bond breaking processes in the same reaction have developed to different extents
as the
transition state is approached along some arbitrarily defined
reaction coordinate. For example, in the nitroalkane anomaly, the Brønsted
exponent for
proton removal is smaller than the Brønsted
for the nitroalkane, because of imbalance between the amount of bond breaking and
resonancedelocalization in the
transition state. Imbalance is common in reactions such as
elimination, addition and other complex reactions that involve
proton (
hydron) transfer.
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1124
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.
https://doi.org/10.1351/goldbook.
