Organobismuths reactions with

Scheme 5 Heck-type phenylation reaction with organobismuth compounds...

Scheme 28 Cross-coupling reaction of organobismuth alkoxides with aryl triflates...

Hypervalent organobismuth compounds 1 bearing a 2,6-pyridinedialkoxide ligand [43] were used for the cross-coupling reaction with aryl triflates (Scheme 28) [44], Phenylation using phenylbismuth compounds smoothly proceeded for the reactive... 

Organobismuth compound 1" was also used for the cross-coupling reaction with alkenyl triflates. CC Et-substituted cyclopentenyl triflate afforded the coupling product quantitatively, while the sterically hindered triflate gave the product in poor yield (Scheme 39) [44], Azabismocine 2 reacted with activated alkenyl chlorides to give the coupling products in moderate to good yields (Scheme 40) [54],... 

Fig. 2 Plausible mechanism for the cross-coupling reaction of organobismuth compounds with organic halides and triflates...

Scheme 53 Reaction of organobismuth compounds with vinyl epoxides...

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. ... 

Nitrosobenzene was also used as a quantitative spin trap for phenyl free radicals, to study their involvement in arylation reactions with organobismuth reagents. Again, ESR observations indicated the formation of phenyl free radicals. However, quantitative trapping measurements showed that only a small amount of free radical derived adducts (2-3%) was formed. The yield of C-arylated products was not affected by the presence of this free radical trap. ... 

The 0-arylation of hydroxyl groups is obtained by reaction either with pentavalent organobismuth and catalytic copper or by reaction with trivalent organobismuth and stoichiometric copper diacetate, acting as an oxidant. 

The transition metals and their salts and coordination complexes such as RhCla, Pd(PPh3)4, Pd(OAc)2, Cu(0), CuCl and CuX2 can catalyze the aryl-aryl coupling, carbonylation and phenylation reactions of organobismuth compounds with indoles, acyl chlorides, acetylenes and olefins, as illustrated in Table 5.12. Most of these reactions proceed under mild conditions. 

---