Trimetallic ReBiPt complexes containing spiro-bismuth ligands from the reaction of the bis(tri-t-butylphosphine)platinum with Re3(CO)12(μ-BiPh2)(μ-H)2

Pt(P-t-Bu3)2 reacts with the bismuthtrirhenium complex Re3(CO)12(μ-BiPh2)(μ-H)2, 1 at 68 °C to give eight complexes PtRe2(CO)9P(t-Bu3)(μ-H)2, 2, PtRe3(CO)12P(t-Bu3)(μ-Ph)(μ-H)(μ4-Bi), 3, PtRe3(CO)13P(t-Bu3)(μ4-Bi)(μ-H)2, 4, PtRe4(CO)16P(t-Bu3)(μ-H)2(μ4-Bi)(μ3-Bi), 5, Pt2Re5(CO)21[P(t-Bu)3]2(μ-H)3(μ4-Bi)2, 6, trans-Pt2Re5(CO)22[P(t-Bu)3]2(μ-H)3(μ4-Bi)2,trans-7, cis-Pt2Re5(CO)22[P(t-Bu)3]2(μ-H)3(μ4-Bi)2, cis-7, (an isomer of trans-7) and Re3(CO)13[PtPBut3]2(μ-H)2(μ4-Bi), 8, all in low yields. When 4 was treated with Pt(P-t-Bu3)2 at 68 °C, compounds 2, trans-7, cis-7, and Pt2Re4(CO)18[P(t-Bu)3]2(μ-H)2(μ4-Bi)2, 9 were formed. When 8 was treated with CO at 25 °C, compounds 2, trans-7, 9, and PtRe3(CO)9P(t-Bu)3(μ3-Bi)(μ4-Bi2), 10 were formed. In all of the products both of the phenyl rings from the bridging BiPh2 ligand of 1 were cleaved from the bismuth atom. Only compound 3 contains a phenyl ligand and that ligand was a bridging ligand across the Pt–Re bond. All of the products, except 10, and the known compound 2, contain spiro, μ4-Bi ligands. The higher nuclearity complexes 5, 6, trans-7, cis-7, and 9 contain two bismuth ligands. Compound 10 contains three bismuth atoms. Two of the bismuth atoms in 10 are part of an octahedrally-shaped Re3PtBi2 cluster. The third bismuth atom is a triply-bridging ligand on the triangular Re3 face of the cluster. When a mixture of 4 and 8 was heated to 68 °C in the presence of CO, the new compound PtRe4(CO)17(P-t-Bu3)(μ-H)2(μ4-Bi), 11 was formed. The molecular structures of all of the new complexes were characterized by single-crystal X-ray diffraction analyses.

The first trimetallic ReBiPt complexes were obtained from the reaction of Pt(P-t-Bu3)2 with the bismuthtrirhenium complex Re3(CO)12(μ-BiPh2)(μ-H)2, 1. Seven of these new complexes contain containing tetra-coordinate quadruply-bridging spiro-bismuth ligands formed by the cleavage of the phenyl groups from the BiPh2 ligand in 1.Figure optionsDownload as PowerPoint slide