Titanium complexes crystallography

Addition of TiCl4 to a solution of trimethylsiloxyphenylisocyanide in //-hexane yields the air sensitive octahedral diisocyanide complex TiCl4(CNR)2 (Scheme 114). This complex crystallizes with one molecule of //-hexane. Its molecular structure has been determined by X-ray crystallography.227 The formations of isocyanide titanium complexes are studied as species related with the Passerini reaction assisted by TiCl4. Three classes of compounds were identified and exemplified by isolated complexes (Scheme 115).228... 

The ionic fulvalene titanium complex [ CpTi(H2O) 2(/i-Ci0H8)(/i-O)]2+[OTP]2 l/2THF (Scheme 591) can be prepared as an air stable compound by the reaction of binuclear [CpTi(/i-H)]2(//-C10H8) with trifluoromethane-sulphonic acid in the presence of small amounts of water. A reaction intermediate is [TiCp(OTf)2]2(//-Ci0H8). The molecular structure of the fi-oxo aquo fulvalene complex has been confirmed by X-ray crystallography.1534... 

Figures 5-41 and 5-42 compare CpTiCp (centroid) bond angles in titanium cyclopentadienyl dichloride complexes from PM3 and BP/ 6-31G calculations, respectively, with experimental values for these and other compounds dealt with in this section from X-ray crystallography. Due to practical limitations, the data used for comparison with the density functional calculations are a subset of that used in comparison with PM3. Both models perform well in separating those systems where the cyclopentadienyl rings are spread far apart from those where they are closer together.

Titanium(IV)-porphyrin [TiO(TPP)] as well as molybdenum(V)-porphyrin [MoO(OMe)(TPP)] complexes were found to be active for the catalytic epoxidation of alkenes by alkyl hydroperoxides, whereas their peroxo derivatives are inactive.632 Iron(III)-porphyrin-peroxo complexes such as Fe(TPP)02NMe4 did not react with hydrocarbons, but form sulfato complexes upon reaction with S02.632 Manganese(III)-porphyrin-peroxo complexes Mn(02)(TPP) K+ were recently characterized by X-ray crystallography.634... 

The titanium carboxylates [CpTi(OCOR)2]2 (R= H, Ph) are obtained when titanocene (CpTiH)2(G10H8) reacts with carboxylic acids the three bridge groups are replaced by four carboxylato bridges (Scheme 415). The structure of the resulting formiato complex has been determined by X-ray crystallography.995... 

A new and facile synthetic method to prepare complexes with Ti-S bonds is based on the oxidation of the low-valent titanium sandwich complex CpT CyHy) with dithiocarboxylic acid to give the Ti(iv) dithioacetate CpTi(S2CMe)3 (Scheme 421). The compound has been fully characterized including X-ray crystallography. It consists of discrete seven-coordinate molecules with a slightly distorted pentagonal-bipyramidal coordination... 

The synthesis, structural determination, and reactivity of ( -symmetric ethylene-bridged titanium compounds has been investigated (Scheme 645). The complexes have been characterized by X-ray crystallography and applied as catalysts for the enantioselective isomerization of alkenes, though they prove to be less enantioselective than the known chiral ansa-bis-Ind titanium catalyst.1667... 

New hydrogenated tetrahydroindenyl and substituted Ind titanocene complexes have been synthesized in an effort to modify the steric environment around the titanium atom in complexes containing chiral bridges connecting two binaphthyl substituted Ind ligands (Scheme 658). The molecular structure of some of these complexes has been determined by X-ray crystallography, -symmetry is observed in the solid state, although in solution at room temperature the NMR spectra indicate 6 -symmetry.1678... 

Hydrolysis of titanocene produces the complex [Cp(C5H4)TiOH]2 X-ray crystallography has established that this has the fulvalene structure (1) characteristic of the titanocene molecule (Vol. 4, p. 2) and that the titanium atoms are bridged by the two hydroxy-groups/ ... 

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