Annulation of indole via indole radicals: addition of the 2-indolyl radical to aromatic rings

The reactions of the radicals derived from indoles 4 are described leading to a short synthesis of fused [1,2-a]indoles via radical addition to the benzene ring followed by rearomatisation whilst one example undergoes an unusual radical translocation/addition reaction. (C) 2000 Elsevier Science Ltd. All rights reserved.