Crystal structure of 3-(tri-phenyl-phosphoranyl-idene)-2,5-di-hydro-furan-2,5-dione tetra-hydro-furan monosolvate.

The title pseudo-polymorph of 3-(tri-phenyl-phospho-ranyl-idene)-2,5-di-hydro-furan-2,5-dione crystallizes with a tetra-hydro-furan solvent mol-ecule, viz. C22H17O3P·C4H8O. The succinic anhydride ring is approximately planar (r.m.s. deviation = 0.032 Å). The tetra-hydro-furan mol-ecule is disordered over two orientations about a pseudo-twofold axis with refined occupancy ratio 0.718 (4):0.282 (4). In the crystal, C-H⋯O hydrogen bonds link mol-ecules of the di-hydro-furan-2,5-dione derivative into chains parallel to the b axis and arranged into layers stacked along [100] alternating with hydrogen-bonded tetra-hydro-furan layers.