Crystal Structure of Diaqua(1,2-bis(2-(o-hydroxy-phenoxy)ethyloxy)ethane)(isothiocyanato)strontium Thiocyanate

Abstract

The aqua complex of podand 1,2-bis(2-(o-hydroxyphenoxy)ethyloxy)ethane (L) with strontium thiocyanate of the composition [Sr(NCS)L(H2O)2]+ · SCN– (I), was synthesized and studied by X-ray diffraction analysis: space group P 21/c, a = 17.730 A, b = 8.558 A, c = 18.169 A, β = 116.15°, Z = 4. The structure was solved by direct method and anisotropically refined by the full-matrix least-squares method to R = 0.039 for 4333 independent reflections (CAD4 autodiffractometer, λMoKα). Structure I contains complex cation [Sr(NCS)L(H2O)2]+ of the host–guest type. The coordination polyhedron of Sr2+ cation (coordination number 9) is a distorted pentagonal bipyramid with four oxygen atoms at the benzene rings of the L podand and the oxygen atom of one water molecule in its base, the N atom of the SCN– ligand at its single vertex, and with the remaining two O atoms of the L podand and O atom of another water molecule at a “triple vertex.” In a crystal, the complex cations and SCN– anions are joined through the hydrogen bonds to form bulky layers parallel to the xy plane.