Rhodium-catalyzed rapid synthesis of substituted phenols from cyclobutenones and alkynes or alkenes via C-C bond cleavage

A novel rhodium-catalyzed synthesis of substituted phenols by the ring-opening reaction of cyclobutenones with alkynes as well as electron-deficient alkenes has been developed. Both reactions involve C-C bond cleavage of cyclobutenones, and an (eta(4)- vinylketene)rhodium complex rather than a rhodacyclopenterione is considered to be a key intermediate. (c) 2007 Elsevier Ltd. All rights reserved.