Synthesis and crystal structure of tetraphenylphosphonium isocyanurate pentahydrate

The disordered crystal structure of tetraphenylphosphonium isocyanurate pentahydrate (Ph4P)+(C3H2N3O3)− · 5H2O was studied by X-ray diffraction. The monoclinic structure (space group C2/c, a = 16.236 Å, b = 7.444 Å, c = 22.712 Å, β = 92.22°, Z = 4) was solved by direct methods and refined by full-matrix least-squares calculation in the anisotropic approximation to R = 0.084 for all 2670 measured independent reflections (CAD4 automated diffractometer, λMoKα). The Ph4P+ crystal is located on a twofold crystallographic axis and the P atom has a distorted tetrahedral coordination. The planar isocyanurate anion is positioned around a crystallographic inversion center and is statistically disordered with respect to the center. The structure of the crystals of anhydrous tetraphenylphosphonium isocyanurate differs from the pentahydrate structure.