Synthesis and characterisation of bis(salicylato)diisothiocyanato silicates - First example of hexacoordinate silicate dianions with six membered rings

Synthesis of hexacoordinate dianionic silicates [(C7H4O3)(2)Si(NCS)(2)](2-) [BH](2)(+) [B=Py(1), 3-MePy(2), 4-MePy(3)] bearing six membered rings arou nd a silicon atom are reported. The complexes 1-3 are prepared from a react ion between salicylic acid and the appropriate cationic five coordinate sil icon(IV) compounds 4-6. All the compounds are characterised by elemental an alyses, molar conductance data as well as IR and multinuclei (H-1, C-13, Si -29) NMR spectra. FAB mass spectra (NBA matrix) of 1-2 have identified resp ective cations and anions of these complexes. (C) 1999 Elsevier Science Ltd . All rights reserved.