Synthesis and structural characterization of neutral hexacoordinate silicon(IV) complexes with SiO2N4 skeletons.

A series of novel neutral hexacoordinate silicon(IV) complexes with SiO(2)N(4) skeletons (compounds 4-8) was synthesized and structurally characterized by single-crystal X-ray diffraction and solid-state NMR spectroscopy ((13)C, (15)N, (29)Si). The silicon(IV) complexes each contain two bidentate monoanionic O,N Schiff base ligands and two cyanato-N or thiocyanato-N ligands. Compounds 4-8 were prepared from Si(NCO)(4) or Si(NCS)(4), whereby the complex formation involved some unexpected chemical transformations of the ligands.