Neue Tetraaminophosphonium-Salze durch Anionenaustausch in flüssigem Ammoniak Novel Tetraaminophosphonium Salts by Anion Exchange in Liquid Ammonia

[P(NH2)4]Br and [P(NH2)41[N03] have been prepared by anion exchange in liquid ammonia. Single crystals of [P(NH2)4]Br were obtained from an acetonitrile solution in a tempera­ ture gradient between 60 °C and room temperature while attempts to grow single crystals of [P(NH2)4][N 0 3] yielded [P(NH2)4][N 03](OP(NH2)3). Both crystal structures were determined by single crystal X-ray methods at room temperature ([P(NH-))4]Br: P4/nbm, a = 809.2(1), c = 468.1(1) pm, Z = 2, R\ = 0.042, wR2 = 0.077; [P(NH2)4][NÖ3](OP(NH2)3): Pna2,, Z = 4, a = 1023.4(1), b = 1704.7(1), c = 618.0(1) pm, R \ =0.025', wR2 = 0.067. In the solid [P(NH2)4]Br forms a tetragonally distorted variant of the CsCl type of structure. [P(NH2)4][N 0 3](0P(N H 2)3) consists of [P(NH2)4]+cations, [N 0 3]_ anions, and OP(NH2)3 molecules which are interconnec­ ted by a complex system of hydrogen bonds.