Crystal and molecular structure of 5,5-BIS(hydroxymethyl)-2-OXO-2-[l-(2-trifluoromethyl-3,3,3-trifluoropropioneamido)-1-trifluoromethyl-2,2,2-trifluoroethyl]-1,3,2-dioxaphosphorinane

The crystal and molecular structure of 5,5-bis(hydroxymethyl)-2-oxo-2-[1-(2-trifluoromethyl-3,3,3-tri-fluoropropioneamido)-1-trifluoromethyl-2,2,2-trifluoroethyl]-1,3,2-dioxaphosphorinane (I) - an effective inhibitor of phosphorolytic enzymes - has been determined by X-ray diffractometry. Crystals I are monoclinic: space group P21/c, a = 9.962(3), b = 20.468(3), c = 9.527(3) å, Β = 108.04(2)ℴ, Z = 4; R = 0.061 for 3065 independent reflections with I ≥ 3Σ. In a sterically strained molecule I, the coordination polyhedron of the P atom is a distorted tetrahedron with an elongated exocyclic P-C bond [1.906(2) å]. The six-membered heterocycle of I has a distorted chair conformation with a significantly flattened angle at the P atom. In the crystal structure, molecules I are linked into centrosymmetric H-dimers by a pair of strong H-bonds of O-H...O=P type and also into infinite (along the z axis) chains by H-bonds of N-H...O = C and C-H...O = C type.