Cp*TiCl

Various methods (e.g., see above), typically redxi. of Cp TiCl. Probably present in reaction products reported earlier as "titanocene ) (see text). 

Addition of [o-(CH2)2C6H4]Mg(THF)2 to Cp TiCb in toluene gives the expected o-xylidene complex Cp TiCl[o-(CH2)2C6H4], However, reaction of [o-(CH2)2C6H4]Mg(THF)2 with Cp TiCb in THF leads to the dinuclear bis(diene)titanium complex (15), in which two Cp TiCl fragments bond to o-xyhdene through its exo- and... 

Epoxides can also be reductively opened to form a radical. An example of an intramolecular cyclization of such a radical has recently been reported <06TL7755>. Treatment of 40 with Cp TiCl generates an intermediate alkoxy radical, which then adds to the carbonyl of the formate ester. The product, 41, is formed as a 2 1 mixture of isomers at the anomeric carbon. This reaction is one of the first examples of a radical addition to an ester. The major byproduct of this reaction is the exo-methylene compound, 42, arising from a P-hydrogen elimination. 

A solution of Cp TiCl [52] (0.43 g, 2 mmol) in THF was added dropwise to a solution of the epoxide (1.0 mmol) in 20 mL of THF at room temperature. A solution of 1A HCl in ether (4 mL) was added, and the mixture was stirred for 10 min. The precipitated solid was removed and the filtrate was added to excess (5 mL) of aqueous saturated sodium di-hydrogenphosphate. The organic layer was separated and the aqueous layer was extracted with ether. The product was isolated as a mixture of exo- and endo-Mt isomers in 70% yield. The structures were confirmed by C-NMR, H-NMR, chemical shift correlation mapping, nOe measurements, and attached proton test (APT) experiments. No [a] was recorded because the product was isolated as a mixture. 

Conjugate addition. Formation of Y,y-dicyanobutanoic esters from alkylidenemalononitriles and bromoacetic esters is effected by Cp TiCl -Zn (13 examples, 43-93%). 

Low-valent group 4 metal derivatives might be prepared from mono-Cp titanium(iv) derivatives by mild reductive conditions. The tetracarbonyltitanates(O) [Cp Ti(CO)4] (Cp = Cp, Cp ) are prepared as Et4N+ salts in 40-50% yield by reduction of Cp TiCL with alkali metal naphthalenides at low temperature, followed by carbonylation at atmospheric pressure. Increased yields of up to 70% have been obtained when reduction is done in the presence of excess CioH8.429 The reduction of CpTiCl3 with zinc and subsequent treatment with 3 equiv. of potassium... 

The reaction of [Cp TiCl(/z-0)]3 with anhydrous silver salts of a variety of oxyanions (S042-, Cr042-, N03, and Re04 ) in organic solvents leads to the isolation of a series of heterobimetallic compounds (Section 4.05.6).821... 

Cp TCl3 reacts with N-alkyl-N,N-diethanolamine, in the presence of NEt3, to give the chloro dialkoxo amino complexes Cp TiCl[(OCH2CH2)2NR] (R = Me, Bu11) (Scheme 375) as slightly air sensitive and thermally unstable compounds. In the presence of MMAO, these complexes show moderate activities in ethylene polymerization and fairly good activities in syndiotactic styrene polymerization.902... 

This complex is prepared in quantitative yield by treatment of dinitrogen complex, [TiCp 2]2(g"N2) with ethylene [95]. Alternatively, reaction of Cp, TiCL with 2 equivalents of n-BuLi under ethylene affords Cp 2Ti(CH2=CH2) in 43% yield [21 Ij. 

Crystal structures of titanium complexes 36a, 36b and 36c and of hafnium complex 36d indicate that the diene-metal interaction is best characterized by the <7, n bonding mode. In general, the diene ligand adopts an s-cis supine conformation with respect to the Cp ligand (e.g. 36c and 36d). However, Nakamura and coworkers have noted that the Cp TiCl complexes of butadiene (36a), 1,3-pentadiene and 1,4-diphenyl-... 

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