A new performance of the reaction of PCl3/AlCl3 with anisoles - One-pot and multi-step syntheses of a new fused-ring system [1,2,3]benzoxadiphospholo[2,3-b][1,2,3]benzoxadiphosphole

Anisoles 4 react with AlCl3 and PCl3 to yield the new fused bicyclic system derivatives 5 and 6 as major products in a one-pot procedure. An alternative multi-step synthesis of this system is also reported in which bis(o-methoxyaryl)phosphane oxides 11 are treated with AlCl3 and PCl3; the diarylphosphane oxides 11 are obtained by a new simple method. © Wiley-VCH Verlag GmbH, 2001.