Chlorotitanium tris

We have prepared a number of titanium enolates by quenching the lithium analogs withchlorotitanium triisopropoxide 3, chloro- or bromotitanium tris(diethylamide) 15 or chlorotitanium tris(dimethylamide) 103 25). In mqst cases the solutions can be freed from the ether or THF and the stable liquid titanium enolates studied by NMR if so desired. In case of the amino derivative 186 flash distillation is possible. The H-NMR spectra of the distilled and non-distilled compound are identical and... 

If carbanions are to be titanated, alkoxy or amino ligands at titanium are most likely to ensure success. Sulfur or phosphorus ligands have not been tested. In rare cases electrontransfer instead of titanation sets in, forming Ti(III) species which are generally unsuitable for useful chemistry. This is most likely to occur if the carbanion is very electron rich, e.g., in case of dianions or extended anionic K-systems. We have noticed that this undesired property decreases in going from chloro to alkoxy and finally to amino ligands at titanium. For example, dianions derived from carboxylic acids reduce chlorotitanium triisopropoxide 3 to some extent, whereas quantitative double titanation occurs with chloro- or bromotitanium tris(diethylamide) 15 77>. Addition of amines to the reaction mixture has similar effects 77). 

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