Abstract
Catalytic cyclization of cis-1-ethynyl-2-vinyloxiranes was implemented with TpRuPPh 3 (CH 3 CN) 2 PF 6 catalyst (10 mol%), to give 2,6-disubstituted phenols in reasonable yields. Under similar conditions, 1,1,2,2-tetrasubstituted oxirane gave the 2,3,6-trisubstituted phenol with skeleton reorganization. On the basis of 2 H- and l3 C-labeling results, we propose that the reaction mechanism involves electrocyclization of ruthenium-vinylidene intermediate with cleavage of the carbon-oxygen bond of the epoxide. © Georg Thieme Verlag Stuttgart.