Chemistry Reference
In-Depth Information
Dissociation leads to aryloxy radicals or to two new radicals that couple. Quinone ketals are
formed initially. They dissociate to yield the original aryloxy radicals and then couple [
102
]:
+
O
O
O
O
O
O
O
O
+
O
Formation of aryloxy radicals as intermediates was established with ESR spectroscopy studies that
showed presence of bothmonomeric and polymeric radicals in the reactionmixture [
103
]. Coupling occurs
by two paths. One of them through rearrangements and the other one through redistribution. In the
redistribution process, two aryloxy radicals couple to yield an unstable quinone ketal as shown above
[
102
]. This ketal decomposes rapidly either back into the original aryloxy radicals or into two different
aryloxy radicals as follows:
O
O
O
O
+
O
O
O
O
O
O
O
O
O
O
quinnnone ketal
+
O
OH
O
O
O
