Spring 2009. Dr. Halligan CHM 236. Chapter 15. Radical Reactions. 1. 1. Introduction. A significant group of reactions involve radical intermediates. A radical is a reactive intermediate with a single unpaired electron, formed by homolysis of a covalent bond.
The relative stability of 1°
and 2° carbon radicals
Reaction of a Radical X• with a C=C Bond.
*Monobromination follows the same mechanism.
Radical fluorination and iodination are not synthetically useful reactions.
CFCs and the
of the ozone layer
Thus, an alkene with allylic C—H bonds undergoes two different reactions depending on the reaction conditions.
Why does a low concentration of Br2 (from NBS) favor allylic substitution (over ionic addition to form the dibromide)?
The oxidation of unsaturated
lipids with O2