[Benzilato(2−)-O1,O2]bis[1,3-diphenylpropane-1,3-dionato(1−)-O,O]silicon(IV): a neutral heteroleptic hexacoordinate silicon(IV) complex with an SiO6 skeleton

Reaction of tetramethoxysilane with 1,3-diphenylpropane-1,3-dione and benzilic acid (molar ratio 1:2:1) in tetrahydrofuran/n-pentane yielded the neutral heteroleptic hexacoordinate silicon(IV) complex [benzilato(2−)-O1,O2]bis[1,3-diphenylpropane-1,3-dionato(1−)-O,O]silicon(IV) (5). Compound 5 was structurally characterized by single-crystal X-ray diffraction, solid-state VACP/MAS NMR spectroscopy (29Si), and solution NMR spectroscopy (1H, 13C, 29Si). The chiral silicon(IV) complex, with its octahedral SiO6 coordination polyhedron, is configurationally stable in solution on the NMR time scale (solvent: CDCl3; maximum temperature studied: 58 °C).