From triorganylbismuth dihalides

The most convenient method for the preparation of pentaarylbismuth is the reaction between triarylbismuth dichloride and 2 equiv. of aryllithium [90B-S]. 

Pentamethylbismuth is prepared from trimethylbismuth dichloride and methyllithium [94AG(E)976]. Pentaorganylbismuth compounds can be transformed into lithium hexaorganylbismuthates by further action of organo-lithium reagent [93IC3948, 94AG(E)976]. 

A solution of 2-fluoroplienyllitliium (6 mmol, freshly prepared from 1 -bromo-2-fluorobenzene and butyllithium at —78°C) in anhydrous diethyl ether was fed through a small Teflon tube into a stirred suspension of triphenylbismuth dichloride (3 mmol) in the same solvent (20 ml) cooled to —78°C. The resulting suspension was gradually warmed to room temperature under stirring. After decanting from deposited lithium chloride, the clear red-violet solution was carefully evaporated. Crystallization at 0°C afforded bis(2-fluorophenyl)triphenylbismuth (45%), which is readily soluble in ether, but insoluble in pentane and sensitive to hydrolysis [90AG(E)213]. 

Pentaphenylbismuth is formed in low yield by the reaction of a triphenylbismuthine imide with two equiv. of phenyllithium [64CB789]. 

Pentamethylbismuth is very unstable and explodes on rapid warming to room temperature in the crystalline state [94AG(E)976]. In solution, it decomposes to trimethylbismuthine. Although pentaphenylbismuth is thermally less stable than its phosphorus, arsenic and antimony congeners, it is still stable 

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