SYNTHESIS AND CHARACTERIZATION OF ARYL BISMUTH COMPOUNDS USING 2,4,6-TRIPHENYLPHENYL AS A BULKY LIGAND

Reaction of BiCl3 with 2,4,6-triphenylphenyllithium in THF solution in a 1:3 ratio, or in toluene solution in a 1:2 ratio affords tris(2,4, 6-triphenylphenyl)bismuth (1) and bis(2,4,6-triphenylphenyl)bismuth chloride (2) respectively. 1 can be recrystallized from THF; the crystal structure has been determined with a yellow crystal of composition (1) 4.8THF (3). The comproportionation reaction of 1 with BiCl3 in a 1:2 ratio, or of 2 with BiCl3 in a 1:1 ratio gives 2,4,6-triphenylphenylbismuth dichloride (4). Reduction of 2 with sodium in ammonia, with magnesium in THF, or with cobaltocene in toluene leads only to the isolation of 1,3,5-triphenylbenzene. Similarly, the reduction of 4 with sodium in ammonia, or with magnesium in THF leads only to 1,3,5-triphenylbenzene as a decomposition product, however, reducing 4 with cobaltocene in toluene affords 1, the latter presumably resulting from a disproportionation reaction of a (not isolated) monovalent bismuth compound, e.g. ''2,4,6-triphenylphenylbismuth (I)'' (6).