Transformation of the substituted group

O-terf-Butyldimethylsilyl groups on the side chains in triarylbismuthines are deprotected by tetrabutylammonium fluoride or p-toluenesulfonic acid to yield non-ionic water-soluble triarylbismuthines bearing neutral hydroxyl groups [98JCS(P1)2511]. 

Synthesis of tris 2-[7V -bis(2-hydroxyethyl)sulfamoyl]phenyl bismuthine 

To a THF solution (15 ml) of tris 2-[MA -bis(2-tcrr-butyldimethylsiloxy)ethyl]sulfamoyl)phe-nyl)bismuthine (355 mg, 0.218 mmol) was added tetrabutylammonium fluoride (THF solution 1.35 ml, 1.35 mmol) at 0°C and the resulting mixture was stirred at room temperature for 3 h. Saturated aqueous NH4CI (15 ml) was added and the organic phase was removed by decantation. The aqueous phase was washed with ether (10 ml X 2) and then allowed to stand overnight. The deposit was filtered off, washed with water and recrystallized from 6% ethanol-water to yield tris 2-[/V,A -bis(2-hydroxyethyl)sulfamoyl]phenyl)bismuthine (125 mg, 61%), m.p. 202-204°C [98JCS(P1)2511]. 

Dimethyl(4-methylphenyl)bismuthine (2 g) was allowed to stand for 3 weeks at room temperature and then heated at ca. 90°C under a stream of nitrogen (to remove trimethylbismuthine). Methylbis(4-methylphenyl)bismuthine was obtained as a colorless solid (100%) [85ZN(B)1476]. 

Compound RjBi R Synthetic method Yield (%) M.p. CO or b.p. (°C/mmHg) 

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