Synthesis and characterization of new phenylbis(salicylato)bismuth(III) complexes

Compounds with the compositions [BiPh(Hsal)(2)] (1a) and [BiPh(Hsal(4Me))(2)] (1b) were prepared by the reactions of triphenylbismuth with 2-hydroxybenzoic acid (H(2)sal) and 4-methyl-2-hydroxybenzoic acid (H(2)sal(4Me)), respectively, in a 1:2 ratio. The reactions of 1a,b with the bidentate nitrogen donor ligands 1,10-phenanthroline (phen) and 2,2'-bipyridine (bipy) led to the isolation of the corresponding adducts [BiPh(Hsal)(2)(phen)] (2a), [BiPh(Hsal(4Me))(2)(phen)] (2b), [BiPh(Hsal)(2)(bipy)] (2c), and [BiPh(Hsal(4Me))(2)(bipy)] (2d). Crystallographic analyses of the adducts showed the solids to have monomeric structures with six-coordinate Bi(III). One salicylato ligand is coordinated in a monodentate fashion and the other in a bidentate, chelating manner. The phenol oxygen atoms remain uncoordinated in both cases. The coordination geometry around Bi(III) in 2a, 2b center dot Me2CO, 2c, and 2d center dot DMF can be described as distorted pentagonal pyramidal with an apical C atom, while the free space trans to the ipso carbon atom of the phenyl group is believed to accommodate a stereochemically active pair of electrons. The H-1 data demonstrate that the salicylate ligands are fluxional in solution. It was shown that under different reaction conditions a number of bismuth(III) oligomeric, dimeric, and monomeric complexes are produced, including [Bi38O44(Hsal)(26)(Me2CO)(16)(H2O)(2)]center dot 4Me(2)CO, [Bi(Hsal(4Me))(sal(4Me))(phen)](2)center dot 2Me(2)CO ([3](2)center dot 2Me(2)CO), [Bi(Hsal(4Me))(3)(bipy)](2)center dot 4Me(2)CO ([4](2)center dot 4Me(2)CO), and [Bi(Hsal(4Me))(3)(phen)(MeOH)] (5), which attest to a rich chemistry in this system.