Some transition-metal complexes derived from silylated 1,3-diynes

Abstract

The complexes [Mo₂(µ-η²-Me₃SiC₂CCSiMe₃)(CO)₄(cp)₂], [Pt(η²-Me₃SiC₂CCSiMe₃)(PPh₃)₂] and Ru₃(µ₃-η²-Me₃SiC₂CCSiMe₃)(µ-CO)(CO)₉] have been prepared. Further reaction of the first with [Co₂(CO)₈] gives [{Mo₂(CO)₄(cp)₂}{Co₂(CO)₆}(µ-η²:µ-η²-Me₃SiC₂C₂SiMe₃)]. Desilylation of [Co₂(µ-η²-Me₃SiC₂CCSiMe₃)-(µ-dppm)_n(CO)_{6 – 2n}](n= 0 or 1, dppm = Ph₂PCH₂PPh₂) gave [Co₂(µ-η²-RC₂CCH)(µ-dppm)_n(CO)_{6 – 2n}](n= 0, R = H; n= 1, R = SiMe₃ or H). The first dppm complex adds across the M–M bonds in [Re₂(CO)₈-(NCMe)₂] and [Ru₃(CO)₁₂] to give [Re₂(µ-H){µ-η¹:η²;µ-η²-C₂C₂SiMe₃[Co₂(µ-dppm)(CO)₄]}(CO)₈] and [Ru₃(µ-H){µ₃-η¹:η²;µ-η²-C₂C₂SiMe₃[Co₂(µ-dppm)(CO)₄]}(CO)₉], respectively, while both dppm complexes react with [WCl(CO)₃(cp)] to give [Co₂{µ-η²-RC₂CC[W(CO)₃(cp)}(µ-dppm)(CO)₄](R = H or SiMe₃). Auration of the HC₂C₂SiMe₃ complex with [AuCl(PPh₃)]–1,8-diazabicyclo[5.4.0]undec-7-ene gave [Co₂{µ-η²-Me₃SiC₂CC[Au(PPh₃)]}(µ-dppm)(CO)₄]. Addition of HCCCCSiMe₃ to [Ru₃(µ-dppm)₂(CO)₈] gave [Ru₃(µ-H)(µ₃-η¹:η²-C₂CCSiMe₃)(µ-dppm)₂(CO)₅]. The complex [Os₃(CO₁₀(NCMe)₂] reacts with HCCCCSiMe₃ to give isomers of [Os₃(µ₃-η²-HC₂C₂SiMe₃)(µ-CO)(CO)₉]; the mixture reacts with [Co₂(CO)₈] to give one isomer of [Os₃{µ₃-η²;µ-η²-HC₂C₂SiMe₃[Co₂(CO)₆]}(µ-CO)(CO)₉] in which the Co₂ moiety bridges the CCSiMe₃ portion of the diyne. The crystal structures of five of the complexes have been determined.