Titanium complexes with imido ligands

Amidinato-amido chloro complexes, with Ti(IV), 4, 335-336 Amidinato-imido titanium complexes, synthesis, 4, 431 -32 Amidinato ligands... 

Imidazolium ligands, in Rh complexes, 7, 126 Imidazolium salts iridium binding, 7, 349 in silver(I) carbene synthesis, 2, 206 Imidazol-2-ylidene carbenes, with tungsten carbonyls, 5, 678 (Imidazol-2-ylidene)gold(I) complexes, preparation, 2, 289 Imidazopyridine, in trinuclear Ru and Os clusters, 6, 727 Imidazo[l,2-a]-pyridines, iodo-substituted, in Grignard reagent preparation, 9, 37—38 Imido alkyl complexes, with tantalum, 5, 118—120 Imido-amido half-sandwich compounds, with tantalum, 5,183 /13-Imido clusters, with trinuclear Ru clusters, 6, 733 Imido complexes with bis-Gp Ti, 4, 579 with monoalkyl Ti(IV), 4, 336 with mono-Gp Ti(IV), 4, 419 with Ru half-sandwiches, 6, 519—520 with tantalum, 5, 110 with titanium(IV) dialkyls, 4, 352 with titanocenes, 4, 566 with tungsten... 

Imido zwitterionic titanium complexes, Ti=NAr[CH3B(C6F5)3], undergo reaction with carbon dioxide to give isocyanates and symmetrical carbodiimides via a ligand metathesis... 

Thiolato titanium complexes have been developed supported by Cp and phosphinimido ligands, in an attempt to compare their chemical behavior with the corresponding bis-Cp derivatives, using the steric and electronic analogy between Gp and imido functionalities. Compounds of the type CpTi(N=PPr13)(SR2)2 (Scheme 244) are prepared by reaction of the dichloro complex with the corresponding lithium thiolates LiSR, or alternatively by protonolysis of Ti-Me... 

Scheme 14.138). A ligand accelerating effect has been observed with the titanium bis (sulfonamide)imido complex. This complex can promote the reaction at room temperature with reaction rate comparable to that of its precursor, supporting the hypothesis of a catalytically active titanium imido intermediate. 

Imido complexes of titanium, supported by cyclooctatetfaene ligands, react with phenyl isothiocyanate across the C=S bond via a [2-t-2] cycloaddition reaction to give a four-membered ring metallacycle . 

Titanium imido complexes supported by amidinate ligands form an interesting and well-investigated class of early transition metal amidinato complexes. Metathetical reactions between the readily accessible titanium imide precursors Ti( = NR)Cl2(py)3 with lithium amidinates according to Scheme 84 afforded either terminal or bridging imido complexes depending on the steiic bulk of the amidinate anion. In solution, the mononuclear bis(pyridine) adducts exist in temperature-dependent, dynamic equilibrium with their mono(pyiidine) homologs and free pyridine. 

Bis-NHC CNC-type pincer ligands were first used with Pd and, later on, coordinated onto early-transition metal complexes. The titanium (III) complex 35 was readily prepared from (THF)3TiCl3 and the free bis(carbene)pyridine, whereas the imido Ti complex 36 was obtained from Ti(NtBu)Cl2(pyridine)3 (Scheme 14.19) [66,67]. The pincer complex 35 was tested in ethylene polymerization. With 500 equivalents of MAO cocatalyst, an activity of 791kgmor bar h was observed. 

Several other studies have been reported on the utilization of P=N motif eontaining ligands. Thus, a titanium-imido complex (32) was stabilized by bis(iminophosphoranyl)methanide ligands. This complex undergos dynamic isomerization. Also, complex (32) displayed modest catal3rtic activity in the reaction of aniline with phenyl acetylene. ... 

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