Abstract
A new method for the generation of C-2 centered radicals derived from 1,3-dithiane
is presented. The radical precursors, 2-dialkylaminoxyl-1,3-dithianes, are readily
prepared from 1,3-dithiane and stable nitroxides. Thermal reaction of 2-dialkylaminoxyl-1,3-dithianes
with electron-deficient olefins affords carboaminoxylation products or oxidative addition
products depending on the nitroxide used. The 2-dialkylaminoxyl-1,3-dithianes can
also be used as initiators/regulators for the controlled living free radical polymerization
of styrene.
Key words
radical chemistry - nitroxides - 1,3-dithianes - controlled radical polymerization
- microwaves
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