SYNTHESIS AND CRYSTAL-STRUCTURES OF (BENZ YL)TRIPHENYLPHOSPHONIUM BROMIDES, [C6H5-CH2P(C6H5)(3)]BR--) AND [C6H5-CH2P(C6H5)(3)]BR-+(3)-(()

(Benzyl)triphenylphosphonium bromide, [C6H5-CH2P(C6H5)(3)]Br-+(-)(CH2C l2) (1) has been prepared by the reaction of triphenylphosphine with b enzylbromide and its structure determined. The colorless crystals are triclinic, space group P (1) over bar, Z = 2, a = 976.0(3), b = 1069.0 (3), c = 1226.1(4) pm, alpha = 94.13(3), beta = 104.70(3), gamma = 100 .14(3)degrees. The lattice contains Br- anions and [C6H5-CH2P(C6H5)(3) ](+) cations. [C6H5-CH2P(C6H5)(3)]Br-3 (2); has been obtained by treat ing compound 1 with equimolar quantities of elemental bromine in methy lene chloride solution. The red crystals of 2 are monoclinic, space gr oup P2(1)/c, Z = 4, a = 917.9(2), b = 1022.6(2), c = 2573.6(5) pm, bet a = 99.11(2)degrees, and comprise[C6H5-CH2P(C6H5)(3)](+) cations and l inear, slightly asymmetrical Br-3(-) anions with bromine-bromine dista nces of 246.19(11) and 263.69(11) pm.