The primary
reference atom in a mechanistic change; usually either of the two atoms of a transformed multiple bond or the single atom at which substitution occurs.
Source:
PAC, 1989, 61, 23
(System for symbolic representation of reaction mechanisms (Recommendations 1988))
on page 55
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.
