Influence of Benzannulation on Metal Coordination Geometries: Synthesis and Structural Characterization of Tris(2-mercapto-1-methylbenzimidazolyl)hydroborato Cadmium Bromide, {[Tm^MeBenz]Cd(μ-Br)}_2.

ABSTRACT: The tris(2-mercapto-1-methylbenzimidazolyl)hydroborato cadmium complex, {[Tm^MeBenz]Cd(μ-Br)}₂, may be synthesized via the reaction of [Tm^MeBenz]K with CdBr₂. X-ray diffraction demonstrates that {[Tm^MeBenz]Cd(μ-Br)}₂ exists as a dimer, which is in marked contrast to the monomeric structure of the non-benzannulated counterpart, [Tm^Me]CdBr, and thereby demonstrates that benzannulation of tris(2-mercapto-1-methylbenzimidazolyl)hydroborato ligands can have a distinct impact on the molecular structure of their metal complexes. In accord with this observation, density functional theory calculations indicate that the benzannulated dimers, {[Tm^MeBenz]Cd(μ-X)}₂ (X = Cl, Br, I), are more stable with respect to dissociation than are their non-benzannulated counterparts, {[Tm^Me]Cd(μ-X)}₂. Furthermore, the calculations also indicate that the stability of the dimer depends on the nature of X, such that the dimer becomes more stable in the sequence I < Br < Cl.

SUBMITTER: Palmer JH 

PROVIDER: S-EPMC4296741 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature