Preparation and crystal structure of tetraphenylphosphonium triiodotetrabromide [PPh4][I3Br4

Tetraphenylphosphonium triiodotetrabromide PPh4]I3Br4] is obtained by the reaction of tetraphenylphosphonium bromide with iodine monobromide. It is the first example of an iodine rich, seven-membered polybromide. PPh4]I3Br4] crystallizes triclinic in the space group P1 with a = 10.947(1) A, b = 11.945(1) A, c = 12.896(1) A, alpha = 66.80(1) degrees, beta = 77.21(1) degrees, gamma = 85.73(1) degrees, and two formula units per unit cell. The final R indices I > 4 sigma(I)] are R1 = 0.0362 and wR2 = 0.0944.