The reactions of M[BF4] (M= Li, K) and(C2H5)2O•BF3 with (CH3)3SiCN.: Formation of M[BFx(CN)4-x] (M= Li, K; x=1, 2) and (CH3)3SiNCBFx(CN)3-,,9-x, (x=0, 1)

The reaction of M[BF4] (M = Li, K) with (CH3)(3)SiCN leads selectively, depending on the reaction time and temperature, to the mixed cyanofluoroborates M[BFx(CN)(4-x)] (x = 1, 2; M = Li, K). By using (C2H5)(2)O.BF3 the synthesis yields the compounds (CH3)(3)SiNCBFx(CN)(3-x) = 0, 1. The products are characterized by vibrational and NMR-spectroscopy, as well as by X-ray diffraction of single-crystals: Li[BF2(CN)(2)].2Me(3)SiCN Cmc2(1), a = 24.0851(5), b = 12.8829(3), c = 18.9139(5) Angstrom V = 5868.7(2) Angstrom(3), Z = 12, R, = 4.7%; K[BF2(CN)(2)] P4(1)2(1)2, a = 13.1596(3), c = 38.4183(8) Angstrom, V = 6653.1(3) Angstrom(3), Z = 48, R-1 = 2.5%; K[BF(CN)(3)] P (1) over bar, a = 6.519(1), b = 7.319(1), c = 7.633(2) Angstrom, alpha = 68.02(3), beta = 74.70(3), gamma = 89.09(3)degrees, V = 324.3(1) Angstrom(3), Z = 2, R-1 = 3.6%; Me3SiNCBF(CN)(2) Pbca, a = 9.1838(6), b = 13.3094(8), c = 16.840(1) Angstrom, V = 2058.4(2) Angstrom(3), Z = 8, R-1 = 4.4%.