Crystal Structure of Complex 1,4,7,10,13-Pentaoxacyclohexadecane-14,16-Dione with Sodium Thiocyanate

The 1,4,7,10,13-pentaoxacyclohexadecane-14,16-dione complex (L) with sodium thiocyanate NaNCS · C₁₁H₁₈O₇(I) was synthesized and studied using X-ray diffraction analysis: space group P2₁2₁2₁, a = 9.519 Å, b = 9.545 Å, c = 17.974 Å, Z = 4. Structure I was solved by the direct method and refined by the least squares method in full-matrix anisotropic approximation to R = 0.051 for all 2690 measured independent reflections (CAD4 autodiffractometer, MoK). The crystal of complex I consists of infinite (along the y axis) polymeric chains formed by [NaL(NCS)] monomeric complexes of the guest–host type. The coordination polyhedron of the Na⁺ cation (coordination number 7) is a distorted pentagonal bipyramid with five ether oxygen atoms of the L ligand in its base and the N atom of the SCN ligand and the carbonyl oxygen atom of the neighboring L ligand on its vertices. In I, the L ligand has crownlike form with a rough mirror symmetry plane passing through its O(7) and C(15) atoms, Na⁺ cation, and N atom of the SCN ligand.