A convenient synthesis of ortho-ortho disubstituted biphenyls containing an eight-membered lactam ring using radical chemistry

Compound 4 prepared from Isatin in two steps underwent an unusual radical-induced rearrangement reaction to yield 9 as the major product and 10 is the minor component. Compound 9 shows structural similarities to the antimitotic agent rhazinilam and the gamma secretase inhibitor LY411575. The scope of the reaction has been studied by changing the substitutions on the aromatic rings and the mechanism for the formation of 9 and 10 from 4 is suggested. (C) 2009 Elsevier Ltd. All rights reserved.