Synthesis of Benzimidazoles Containing a Fused Alicyclic Ring By Rhodium - Catalysed Hydroformylation of N-Alkenyl-1,2-diaminobenzenes

Article abstract of DOI:10.1016/S0040-4020(01)90361-8

Rhodium-catalysed reactions of N-alkenyl-1,2-diaminobenzenes (3) with hydrogen and carbon monoxide give benzimidazoles containing a fused alicyclic ring ((8) and (9)) in excellent yields.In some cases intermediate bicyclic compounds can be isolated and the 1H and 13C n.m.r. spectra of one of these, the 3,4,5,6-tetrahydro-4-methyl-3H-1,6-benzodiazocine (6), shows evidence for unusual atropisomerism.