Titanium and Zirconium Bent-Sandwich Complexes with the New [2-(Diisopropylamino)ethyl]cyclopentadienyl Ligand:  Catalysts for the Polymerization of Ethylene and the Dehydrocoupling of Phenylsilane

Abstract

Dehydrocupling of phenylsilaneMixed bent sandwich titanium(IV) complexes containing the donor-substituted [2-(diisopropylamino)ethyl]cyclopentadienyl (C5H4CH2CH2NiPr2 = CpN) ligand are described. The highly moisture-sensitive metallocene dichloride ( C5H4CH2CH2NNiFV2)(C5H4SiMe3)TiC12 (1) was synthesized by reaction of CpNLi with CpSTiCl3 (Cps = C5hSiMe3). Complex 1 reacts with one equivalent of HCl with protonation of the amino group to give the air-and water-stable metallocene dichloride-hydrochloride [ (C5H4CHzCHz-N(H)iPr2)(C5H4SiMe3)TiC1,]+C1-(2). The structure of 2 was determined by a single-crystal X-ray diffraction study. Com-pounds 1 and 2 are precursors for ethylene polymerization catalysts. The reaction of 2 with one equivalent of Na+B[3,5-(CF3)2C&]: afforded the borate [ (C5H4CH2CH2N(H)Pr2)-(C5H4SiMe3)TiC12]+B[ 33-( CF3)2C6H3]: (3). The dimethyl compound (C5H4CH2CH2NiPr2)(C5H&iMe3)TiMe2 (4) was obtained by reaction of 1 with two epuivalents of methyllithium. The diphenoxy complex (C5H4CH2CH2-NiPr2)(C5H4SiMe3)Ti(OPh)2 (5) was prepared analogously with a stoichiometric amount of lithium phenoxide. Compounds 4 and 5 show remarkable activity in the catalytic dehydrocoupling of phenylsilane.

Functionalised cyclopentadienyl titanium compounds as potential anticancer drugs

“…Compounds 7-10 were characterised by microanalysis, 1 H and 13 C NMR spectroscopy and in the case of 10 X-ray crystallography.The molecular structure of compound 10 is shown in Fig.4and selected bond lengths and bond angles are given in Table3. The N(1)-Cl(3) distance is 2.966 A ˚and the N-H-Cl angle is 178.84 • , which are very similar to the molecular structures of other hydrochloride salts synthesised 4,34.…”

Study on Structural and Thermal Characteristics of Heteroleptic Yttrium Complexes as Potential Precursors for Vapor Phase Deposition

“…This bent‐sandwich like configuration forms Y–N σ‐bonds from the η 2 ‐chelating guanidinate or amidinate ligand and π‐bonds between the Cp units and Y. [19b]…”

Dehydrocondensation of organylsilanes giving Si–Si bonds

“…Silafluorene (5c) is converted into a pentamer, which is insoluble in the usual organic solvents, upon catalysis by dimethyltitanocene in toluene in the absence of oxygen for 29 h. 2 Ti(OPh) 2 , were suggested as efficient catalysts of dehydrocondensation of phenylsilane. 114 Binary mixtures of dimethyltitanocene with one equivalent of trialkyl-or alkylarylphosphine are used as catalysts of dehydrocondensation of PhSiH 3 , MePhSiH 2 , Ph 2 SiH 2 and BnSiH 3. 97 ± 99 In these cases, microcrystalline products are formed.…”