Stereochemistry of Octahedral cis-Tetrafluoro Titanium Complexes with Ph2P(O)CH(Me)CH2C(O)Et Enantiomers in CH2Cl2

Resumo

The complex formation of TiF₄ with the phosphorylated ketone Ph₂P(O)CH(Me)CH₂C(O)Et (L), containing an asymmetric carbon atom in the aliphatic hydrocarbon group and representing a racemic mixture of enantiomers, was studied by ¹⁹F{¹H} and ³¹P{¹H} NMR spectroscopy. The composition of complexes formed in the solution was determined; analysis of the ¹⁹F NMR spectra resorting to the heterotropicity concept was used to assign the resonance lines to two chiral optically active racemic and meso-stereoisomers of cis-TiF₄L₂. The configurations of enantiomers of the monodentate ligand coexisting in the coordination sphere were found to have a crucial effect on the axial fluorine atoms of mixed octahedral cis-tetrafluoro d⁰ transition metal complexes. A new efficient method was developed for the synthesis of ligand L.