The preparation, characterization and reactivity of the cyclometallosilane, cyclo-1,1-di-h5-cyclopentadienyltitana-2,2,3,3,4,4,5,5,-octaphenylpentasilane, (h5-C5H5)2TiSi(C6H5)2[Si(C6H5)2]2Si(C6H5)2

Synthesis of Oligosilanyl Compounds of Group 4 Metallocenes with the Oxidation State +3

“…For the heavier metals zirconium and hafnium six-membered rings should be stable. Although no calculations were carried out for phenyl substituents at the silicon atoms in α positions, the stability of this substitution pattern might be even higher, given the fact that a titanaoctaphenylcyclopentasilane 21,22 and even a titanadecaphenylcyclohexasilane are known. 23,24 The trend outlined here also provides an explanation for the fact that Cp 2 Ti(Cl)SiMe 3 was found to be a stable compound while the synthesis of the analogous tris(trimethylsilyl)silyltitanocene chloride failed.…”

“…Among these compounds Cp 2 Ti­(Cl)­SiMe 3 ( I ), prepared by Rösch et al utilizing the reaction of Cp 2 TiCl 2 with Al­(SiMe 3 ) 3 ·Et 2 O, is well characterized with 1 H and 13 C NMR and IR spectra and a low-quality crystal structure ( R = 16%). The titanacyclosilanes Cp 2 Ti­(SiPh 2 ) n ( n = 4 ( II ), 5 ( III )) − were reported as products of the reaction of Cp 2 TiCl 2 with Li­(Ph 2 Si) n Li. While for Cp 2 Ti­(SiPh 2 ) 4 , 1 H and 13 C NMR spectra in acetone were reported, the formation of Cp 2 Ti­(SiPh 2 ) 5 , was substantiated by multinuclear (including 29 Si) NMR and a crystal structure analysis .…”

“…The titanacyclosilanes Cp 2 Ti­(SiPh 2 ) n ( n = 4 ( II ), 5 ( III )) − were reported as products of the reaction of Cp 2 TiCl 2 with Li­(Ph 2 Si) n Li. While for Cp 2 Ti­(SiPh 2 ) 4 , 1 H and 13 C NMR spectra in acetone were reported, the formation of Cp 2 Ti­(SiPh 2 ) 5 , was substantiated by multinuclear (including 29 Si) NMR and a crystal structure analysis . The reported synthesis of the silylene-bridged complex [Cp 2 Ti­(SiH 2 )] 2 obtained by Weiss from the reaction of Cp 2 TiCl 2 with H 3 SiK was later questioned by Harrod and co-workers, who repeated the published procedure and obtained only [Cp 2 Ti­(SiH 3 )] 2 .…”

Group 4 Metal and Lanthanide Complexes in the Oxidation State +3 with Tris(trimethylsilyl)silyl Ligands

“…Investigations on the chemistry of group 4 silyl complexes were started in the late 1960s, with some work on silyl titanium chemistry − and Lappert’s contributions of zirconocene and hafnocene complexes. − Systematic studies of zirconocene and hafnocene silyl complexes were carried out by Tilley and co-workers, − who especially studied aspects of σ-bond metathesis and the catalytic dehydrocoupling polymerization of hydrosilanes catalyzed by these compounds. − While in the initial papers by Harrod and co-workers − on the dehydrocoupling polymerization of hydrosilanes titanium was acting as the catalytically active element, Tilley’s mechanistic studies were carried out using hafnium or zirconium. Starting out from CpCp*M­(Cl)­Si­(SiMe 3 ) 3 (M = Zr, Hf) it was shown that σ-bond metathesis reaction with a hydrosilane leads to (Me 3 Si) 3 SiH and a new metal silyl complex, which in reaction with another hydrosilane forms a disilane and a metal hydride …”

Synthesis and Characterization of Methoxylated Oligosilyl Group 4 Metallocenes

“…Rösch et al synthesized Cp 2 Ti­(Cl)­SiMe 3 ( I ) by the reaction of Cp 2 TiCl 2 with Al­(SiMe 3 ) 3 ·Et 2 O . Additionally, Cp 2 Ti­(SiPh 2 ) n ( n = 4 and 5 ( II )) was successfully reported by Holtman et al and Igonin et al by the reaction of Cp 2 TiCl 2 with Li­(Ph 2 Si) n Li. − Cp 2 Ti­(SiH 3 ) 2 ( III ) was achieved by Harrod and co-workers by reacting Cp 2 TiCl 2 with H 3 SiK . Also, Marschner and co-workers successfully synthesized a titanocene disilene complex ( IV ) .…”