Titanium dicyclopentadienyls

DIENES Alkylaluminum halides. 1,4-BistrimethylsiIyl-2-butyne. Chlorotnmethylsilan e-Sodium iodide. Dicyclopentadienyl( 1 triniethylsilylallyl (titanium. Dimcthylformamide dimethyl acetal. Sodium dicarbonylcyclopentadienyl ferrate. Titanium(O). Tri-/i-hutyl(iodomcthyl)tin. Trimethylsilyl-allyllitimim... 

Since the hemiacetal 3, can now readily be prepared from cheap commercially available starting materials (vide supra, Eq. (1))7), this reaction constitutes a convenient source of 1-vinylcyclopropanols. Otherwise, the 1-ethynyl-cyclopropanols 9, also easily available from 3 or from its magnesium salt 10 (vide supra, Eq. (4) and (6) underwent either lithium aluminium hydride reduction in refluxing THF to lead exclusively to the E-1-vinylcyclopropanols 69 or reduction with dicyclopentadienyl-titanium hydride in ether at 0.°C, prepared from isobutylmagnesium halides and a catalytic amount of dicyclopentadienyl titanium dichloride (r -CjH TiCk), to yield exclusively the Z isomer 70, Eq. (22) 15,39). 

Transition metal carbodiimides, such as MnNCN and CuNCN, and carbodiimides derived from zinc, mercury,silver and thallium are also known. A preceramic polymeric titanium carbodiimide is obtained in the reaction of TiCU with bis(trimethyl-silyl)carbodiimide. Liganded carbodiimidotitanium complexes are obtained in the reaction of CpaTiCla with Me3SnN=C=NSi(i-Pr)3. ° Also, dicyclopentadienyl titanium (IV) diisocyanates are converted into carbodiimides with LiN(SrMe3)2. ... 

Metal cyclopentadienyls have already proved to be of considerable technical interest. According to investigations carried out mainly in the United States, ferrocene is able to bring about smokeless combustion of fuel oil when added in amounts of 0.05% (1). Its use as an oil additive for jet motors and as an antiknock has also been proposed. Liquid ferrocene is said to have advantages as a thermally stable heat-transfer medium. Dicyclopentadienyl nickel also has possible applications, and dicyclopentadienyl titanium-dichloride has been studied in association with aluminum alkyls for the polymerization of ethylene (15, 133, 134). Finally, the carbonyl CHsC5H4Mn(CO)3 has been considered as a fuel additive in conjunction with tetraethyl lead (0). Other information is given in the patent literature (40). 

Zirconium Neodecanoate Cobalt Pentanedione Ferric Pentanedione Ferrous Dicyclopentadienyl Ferrous Pentanedione Titanium Pentanedione Cobalt Dicyclopentadienyl Vanadium Neodecanoate Ferrous Stearate Ferric Naphthenate Control... 

The previously isolated1654 / // -/rtitanium dichloride has been prepared by a new route, involving the reductive dimerization of 6-phenylfulvene with activated calcium powder followed by treatment with TiCl3/AlCl3 (1 3) and oxidation in air. This complex has been used to synthesize a variety of other // -derivatives through ligand replacement (Scheme 642). The reaction of 6,6-diphenylfulvene... 

At the time we started this mechanism work, one compound was available in the formal titanium (II) state which we thought we would try to use, the so-called titanocene (12). Although in empirical terms titanocene is dicyclopentadienyl titanium, the substance is isolated as a dimer, C2oH2oTi2. In our early work, we actually used a cyclopenta-dienyltitanium species, CioHioTiCl2, for a fixation reaction. Several years ago at Stanford, Stewart Schneller prepared some titanocene and started to carry out fixation experiments. He quickly secured significant results, which were published early in 1969 (II). 

Cano, A. Cuenca, T. Gomez-Sal, R Manzanero, A. Royo, P. Dicyclopentadienyl titanium and zirconium complexes with the double bridged bis(dimethylsilanodiyl)dicyclopentadienyl [(Me2Si)2(ti -... 

Bis(7 --cyclopentadienyl)bis [bis(trifluoromethyl)phosphinoxy Jtitanium, (vr- 5116)2X1 OP(CFs)2 2, is obtained quantitatively from dicyclopentadienyl-titanium dichloride and (CF3)2P 0 P(CF3)2 at 85 °C in toluene in a sealed tube in contrast, titanium tetrachloride undergoes a complex reaction leading to unidentified products under the same conditions. 

QoHioBCUTi Tetrachloroborate dicyclopentadienyl titanium Nr.30,X=B Chemical synthesis from stable components/ Toluene EPR/ 300 1.975 Ti 1.16 B 0.59 69Hen2... 

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