Main group metal halide complexes with sterically hindered thioureas XV. The crystal and molecular structures of two unique monomeric bismuth(III) thiocyanate complexes with 1,3-dimethyl-2(3H)-imidazolethione

Two new bismuth(III) thiocyanate complexes with a sterically hindered thiourea, 1,3-dimethyl-2(3H)-imidazolethione (dmit), have been prepared and characterized via X-ray crystallography and IR spectroscopy. One complex, [Bi(S)NCS(dmit)3] · 2H2O (I), could not be obtained in analytically pure form, but an individual crystal reveals a slightly distorted octahedral structure with one of the water molecules occupying the position trans to the sulfido group. The other complex, [Bi(SCN)(NCS)2(dmit)3] (II), was also a distorted octahedral with the dmit ligands in a meridional configuration. Two of the thiocyanates are N-bonded and the other is S-bonded. IR spectra show characteristic thiocyanate CN stretches correlating to the bonding mode for both complexes, and neither complex shows strong evidence of a stereoactive lone pair.