A second polymorph of bis(triphenyl-λ5-phosphanylidene)ammonium chloride–boric acid adduct

Abstract

The title crystal structure is a new triclinic polymorph of [(Ph3P)2N]Cl·(B(OH)3) or C36H30NP2+·Cl−·BH3O3. The crystal structure of the orthorhombic polymorph was reported by [Andrews et al. (1983). Acta Cryst. C39, 880–882]. In the crystal, the [(Ph3P)2N]+ cations have no significant contacts to the chloride ions nor to the boric acid molecules. This is indicated by the P—N—P angle of 137.28 (8)°, which is in the expected range for a free [(Ph3P)2N]+ cation. The boric acid molecules form inversion dimers via pairs of O—H...O hydrogen bonds, and each boric acid molecule forms two additional O—H...Cl hydrogen bonds to one chloride anion. These entities fill channels, created by the [(Ph3P)2N]+ cations, along the c-axis direction.