193404-94-3Relevant articles and documents
Transition metal silyl complexes part 54 1. Hydrido disilanyl complexes LnM(H)SiR2SiR2H (LnM = MeCp(CO)2Mn, Cp(CO)2Re, (CO)3(PPh3)Fe)
Karch, Ralf,Schubert, Ulrich
, p. 151 - 160 (2008/10/08)
Hydrido disilanyl complexes of the type LnM(H)SiPh2SiPh2H are obtained from HPh2Si-SiPh2H by photochemical reaction with MeCp(CO)3 or by ligand exchange reactions starting from MeCpMn(CO)2(THF), Cp(CO)2Re(THF) or (CO)3(PPh3)Fe(H)SiMe3. The dinuclear complex [MeCp(CO)2Mn(H)SiPh2]2 is additionally obtained in the photochemical reaction of a 2:1 mixture of MeCpMn(CO)3 and HSiPh2SiPh2H. When HMePhSi-SiMePhH or HMe2Si-SiMe2H is used instead of HPh2Si-SiPh2H, the kind of products depends on the metal fragment. Both types of complexes are formed when HMePhSi-SiMePhH is reacted with MeCpMn(CO)2(THF), but only the mononuclear complex is obtained from CpRe(CO)2(THF) or from (CO)3(PPh3)Fe(H)SiMe3. Photochemical reaction of HMe2Si-SiMe2H with MeCpMn(CO)3 yields only the dinuclear complex. The outcome of the reaction of Cp(CO)2Re(THF) with HMe2Si-SiMe2H depends on the reaction temperature. At 25°C only cis-Cp(CO)2Re(H)SiMe2SiMe2H was spectroscopically observed in low concentration. In refluxing THF, cis-and trans-Cp(CO)2Re(H)SiMe2SiMe2H, and [Cp(CO)2Re(H)SiMe2]2 are formed. Reaction of (CO)3(PPh3)Fe(H)SiMe3 with HMe2Si-SiMe2H gives both (CO)3(Ph3P)Fe(H)SiMeSiMe2H and [(CO)3(Ph3P)Fe(H)SiMe2]2. Photochemical reaction of Fe(CO)4PPh3 with HMe2Si-SiMe2H results in the formation of (CO)2(PPh3)2Fe(H)2. The hydride-bridged complex [Cp(CO2)Re]2(μ-H)2 is formed as a by-product in the reactions of disilanes with CpRe(CO)2(THF). Thermal or photochemical decomposition of the complexes LnM(H)SiPh2SiPh2H preferrentially proceeds by reductive elimination of the disilane. Only in the decomposition of MeCp(CO)2-Mn(H)SiPh2SiPh2H some H2 is observed, which may be due to a 1,2-H2 elimination.
