Binuclear organometallic compounds VIII. Oxidative addition of Si-H or Si-Cl compounds to low valent Fe, Co, or Ni complexes stabilised by mono- or bi-dentate phosphines

The reactions of [(Ph 3 P) 4 Ni], [(Ph 3 P) 3 CoN 2 ], [(dp) 2 Ni], [(dp) 2 CoH], [(dp) 2 Fe(C 2 H 4 )] or [(dp) 2 FeH 2 ] (dp = Ph 2 PCH 2 CH 2 Ph 2 P) with Ph n SiCl 4- n ( n = 1, 2, or 3), Ph n SiH 4- n , X 3 SiH (X = Cl or Et), or R 2 ClSiH (R = Ph or Me) have been investigated. Solid complexes were isolated which, for the most part, were insoluble in non-polar solvents. Assignments of structures are therefore incomplete, and are based on microanalysis, IR spectra, analogies with established reactions, and (in some cases) chemical degradation. Evidence is presented for the following: (i) for Ni II , products from [(Ph 3 P) 4 Ni] and HSiXX′X″ (XX′X″ = Ph 3 , Ph 2 H or PhH 2 ), the cyclic [(Ph 3 P) 2 NiSiCl 2 ] 2 , and the five-coordinate [(dp) 2 -NiX] + [SiCl 3 ] - (X = H or Cl 3 Si); (ii) for Co III , the six-coordinate cis -octahedral [(dp) 2 CoH 2 ] + [SiXX′X″] - (XX′X″ = Cl 3 , Cl 2 Me, ClMe 2 , or ClPh 2 ); and for Fe II , the four-coordinate [(dp)FeH(SiCl 3 )] and the six-coordinate [(dp) 2 Fe(X)SiCl 3 ] (X = H, Cl, or Cl 3 Si).