Organobismuth reagents pentavalent

The elementary phenylation reaction with pentavalent organobismuth reagents is itself a two-steps sequence which proceeds first by the formation of a covalent pentavalent substrate-bismuth intermediate. In the second step, this intermediate then undergoes a ligand coupling process. ... 

The number of S- and N-arylations with arylbismuth reagents is relatively limited. The reaction of thiols with pentavalent organobismuth reagents leads mostly to oxidation products and, in some instances, to 5-phenylation. In the case of the nitrogen derivatives, the most efficient arylation by arylbismuth reagents are reactions which are copper-catalysed, and these will be reviewed in a later part of this chapter (see section 6.7). 

Barton, D.H.R., Einet, J.-P, Motherwell, W.B. and Pichon, C. (1987) The chemistry of pentavalent organobismuth reagents. Part 8. Phenylation and oxidation of alcohols by tetra-phenylbismuth esters. Journal of the Chemical Society — Perkin Transactions 1, 251-259. 

The first studies on the application of pentavalent organobismuth derivatives in organic synthesis focused on oxidation reactions. In the course of these studies, when Barton et al treated quinine with triphenylbismuth carbonate (5), the reaction led to a rather modest yield of the expected quininone (34%). Using an excess of the reagent (5) afforded a good yield of a mixture of diastereo-isomeric a-phenylated ketones (75%). 3... 

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