Halogenation of (CF3)3B•NH3:: N,N-dihaloamino- and halo-tris (trifluoromethyl)borates [(CF3)3B-NX2]- and [(CF3)3B-X]-, X = F, Cl, Br

(CF3)(3)B . NH3 (1) reacts with cesium hypochlorite or hypobromite to form the respective N,N-dichloroamina- or N,N-dibromoamino-tris(trifluoromethyl)borates Cs[(CF3)(3)B-NCl2] (2) or Cs[(CF3)(3)B-NBr2] (3). Fluorination of 2 or 3 in CH3CN yields Cs[(CF3)(3)B-NF2] (4) and Cs[(CF3)(3)B-F] (5). The fluorination reactions produce numerous byproducts; one of these, Cs[(CF3)(3)B-NH-COCBr3] (6), has been isolated from the reaction of 3. Compound 5 was also formed when 2 or 3 was treated with AgF2. Pyrolysis of 2 at 190 degrees C and 3 at 140 degrees C. yielded the haloborates Cs[(CF3)(3)B-Cl] (7) and Cs[(CF3)(3)B-Br] (8), respectively. The constitution of the novel berates has been deduced from multinuclear NMR, IR, Raman, and mass spectra. The structures of 6, 7, 8, and Cs[(CF3)(3)B-NH2 x (CF3)(3)B -NH3] (1a) have been investigated by single-crystal X-ray diffraction. 1a: C6H5B2CSF18N2, monoclinic, C2/c, a = 22.802(5) Angstrom, b = 7.0965(13) Angstrom, c = 11.000(2) Angstrom, beta = 102.79(2)degrees, Z = 4, R1 = 0.0374, wR2 = 0.0945. 6: C5HBBr3CsF9NO, monoclinic, C2/c, a = 20.121(4) Angstrom, b = 16.765(3) Angstrom, c = 10.005(2) Angstrom, beta = 118.416(12)degrees, Z = 8 R1 = 0.0680, wR2 = 0.1766. 7: C3BClCsF9, cubic, P2(1)3, a = 9.8059(9) Angstrom, Z = 4, R1 = 0.0252, wR2 = 0.0639, 8: C3BBrCsF9, cubic, P2(1)3, a = 9.9001(14) Angstrom, Z = 4, R1 = 0.0631, wR2 = 0.1490.