Synthesis and crystal structure of 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane bis[dichloro(thiocyanato)copper(II)

Abstract

A new complex salt [4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane bis[dichloro(thiocyanato)copper(II)], [H2(Crypt-222)][CuCl2(SCN)]2, is synthesized and studied by X-ray diffraction analysis. The crystals are monoclinic (space group C2/c, a = 14.603 A, b = 8.330 A, c = 25.091 A, β = 100.76°, Z = 4). The structure is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.047 for 2943 independent reflections (CAD-4 automated diffractometer, λMoK α radiation). The Cu2+ cations and Cl− and SCN− anions form infinite polymeric chains of spiro-conjugated alternating centrosymmetric four-membered CuCl2Cu cycles and eight-membered Cu(SCN)2Cu cycles through coordination bonds. The coordination polyhedron of the Cu2+ cation is a distorted trigonal bipyramid. The [H2(Crypt-222)]2+ dication contains trifurcate N+-(…O)3 bonds on axis 2.