A New Convenient Synthesis of Triarylbismuthanes Bearing Three Different Aryl Groups by the Grignard Arylation of Unsymmetrical Diarylbismuth Triflate−Hexamethylphosphoric Triamide (HMPA) Complexes

Triarylbismuthanes bearing three different aryl groups, Ar1Ar2Ar3Bi (4), have been conveniently synthesized by the action of aryl Grignard reagent Ar3MgBr on unsymmetrical diarylbismuth triflate−HMPA complexes Ar1Ar2BiOTf(HMPA)2 (8), which are readily accessible by the selective cleavage of triarylbismuthanes Ar12Ar2Bi (7; Ar1 is more fugacious than Ar2) with trimethylsilyl triflate in the presence of HMPA.