MAIN-GROUP METAL HALIDE-COMPLEXES WITH STERICALLY HINDERED THIOUREAS .15. THE CRYSTAL AND MOLECULAR-STRUCTURES OF 2 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 prepare d and characterized via X-ray crystallography and IR spectroscopy. One complex, [Bi(S)NCS(dmit)(3)]. 2H(2)O (I), could not be obtained in an alytically pure form, but an individual crystal reveals a slightly dis torted octahedral structure With one of the water molecules occupying the position trans to the sulfide group. The other complex, [Bi(SCN)(N CS),(dmit)(3)] (II), was also a distorted octahedral with the dmit lig ands in a meridional configuration, Two of the thiocyanates are N-bond ed and the other is S-bonded. IR spectra show characteristic thiocyana te CN stretches correlating to the bonding mode for both complexes, an d neither complex shows strong evidence of a stereoactive lone pair.