Crystal structure of the tetraaquabis(thiocyanato-κN)cobalt(II)–caffeine–water (1/2/4) co-crystal

Abstract

In the structure of the title compound [systematic name: tetraaquabis(thiocyanato-κN)cobalt(II)–1,3,7-trimethyl-1,2,3,6-tetrahydro-7H-purine-2,6-dione–water (1/2/4)], [Co(NCS)2(H2O)4]·2C8H10N4O2·4H2O, the cobalt(II) cation lies on an inversion centre and is coordinated in a slightly distorted octahedral geometry by the oxygen atoms of four water molecules and two N atoms of twotrans-arranged thiocyanate anions. In the crystal, the complex molecules interact with the caffeine molecules through O—H...N, O—H...O and C—H...S hydrogen bonds and π–π interactions [centroid-to-centroid distance = 3.4715 (5) Å], forming layers parallel to theabplane, which are further connected into a three-dimensional network by O—H...O and O—H...S hydrogen bonds involving the non-coordinating water molecules.