Pentavalent organobismuth reagents. Part 2. The phenylation of phenols
Abstract
The phenylation of a variety of phenols by pentavalent bismuth reagents under neutral, acid and basic conditions has been investigated. Under basic conditions well defined pentavalent intermediates have been isolated and fully characterised. Their decomposition gives only ortho-C-phenylation (except in the case of a p-nitrophenol derivative). O-Phenylation is seen under neutral or acidic conditions. Another mechanism is proposed to explain this reaction with no pentavalent bismuth intermediate.