Coupling of 1,3-diynes on a triruthenium cluster: reactions of Ru3(m3-PhC2C CPh)(m-dppm)(CO)8 with SiMe3C CC CSiMe3

Abstract

Reactions between Ru3(μ3-PhC2C6-point triple bond; length half of m-dashCPh)(μ-dppm)(CO)8 (1) and SiMe3C6-point triple bond; length half of m-dashCC6-point triple bond; length half of m-dashCSiMe3 have given the complexes Ru2(μ-dppm){μ-C(C6-point triple bond; length half of m-dashCPh)=CPhC(SiMe3)=C(C6-point triple bond; length half of m-dashCSiMe3)}(CO)4 (3), containing the two diynes coupled in head-to-head fashion, Ru3{μ3C(SiMe3)=C(C6-point triple bond; length half of m-dashCSiMe3)C(=CPh)C(=CPh)C(O)}(μ-dppm)(CO)7 (4), containing a metalla–indenone ligand formed by coupling of the two diynes with CO, and Ru4(μ4-PhC2C6-point triple bond; length half of m-dashCPh)(μ4-SiMe3C2C6-point triple bond; length half of m-dashCSiMe3)(μ-dppm)(μ-CO)(CO)8 (6), in which the two diynes are on opposite sides of a puckered Ru4 rhomboid. Also formed were thermolysis products of 1, Ru3{μ3-CPhCHCC(C6H4)}(μ-dppm)(CO)8 (5) (previously described) and Ru4(μ4-PhC2C6-point triple bond; length half of m-dashCPh)(μ-dppm)(CO)10 (7), the dppm-substitution product of Ru4(μ4-PhC2C=CPh)(CO)12. The X-ray determined structures of 3, 6 and 7 are reported.