Morlok Melissa M, Docrat Arefa, Janak Kevin E, Tanski Joseph M, Parkin Gerard
Department of Chemistry, Columbia University, New York, New York 10027, USA.
Dalton Trans. 2004 Nov 7(21):3448-52. doi: 10.1039/B412147C. Epub 2004 Sep 27.
The molecular structure of the tris(2-mercapto-1-tolylimidazolyl)hydroborato complex [[Tm(p-Tol)]Zn(mim(p-Tol))][ClO(4)].3MeCN has been determined by X-ray diffraction, thereby demonstrating that the mim(p-Tol) ligand exhibits a N-H...O hydrogen bond with the ClO(4) counterion, [[Tm(p-Tol)]Zn(mim(p-Tol))...(OClO(3))], rather than hydrogen bond with a sulfur of the [Tm(p-Tol)] ligand. DFT calculations on a series of related complexes, namely [Tm(Me)]Zn(mim(Me)), [[Tm(Me)]Zn(mim(Me))]...(OClO(3))], [[Tm(Me)]Zn(mim(Me))]...[O(H)Me]](+), and [[Tm(Me)]Zn(mim(Me))]...(NCMe)](+) demonstrate that an intramolecular N-H...S hydrogen bond within [Tm(Me)]Zn(mim(Me)) is also less favored than the corresponding hydrogen bonding interactions with MeCN, MeOH, and ClO(4). The inability of the sulfur atoms of [Tm(R)] ligand to act as an effective hydrogen bond acceptor is in marked contrast to the ability of sulfur atoms in thiolate ligands to participate in the formation of N-H...S hydrogen bonds, an observation that reflects the "thione"versus"thiolate" nature of the [Tm(R)] ligand.
通过X射线衍射确定了三（2-巯基-1-甲苯基咪唑基）氢硼酸锌配合物[[Tm(p-Tol)]Zn(mim(p-Tol))][ClO(4)].3MeCN的分子结构，从而表明mim(p-Tol)配体与[ClO(4)]⁻抗衡离子[[Tm(p-Tol)]Zn(mim(p-Tol))...(OClO(3))]形成N-H...O氢键，而非与[Tm(p-Tol)]配体的硫形成氢键。对一系列相关配合物，即[[Tm(Me)]Zn(mim(Me))]⁺、[[Tm(Me)]Zn(mim(Me))]...(OClO(3))]、[[Tm(Me)]Zn(mim(Me))]...[O(H)Me]⁺和[[Tm(Me)]Zn(mim(Me))]...(NCMe)]⁺进行的密度泛函理论计算表明，[[Tm(Me)]Zn(mim(Me))]⁺内的分子内N-H...S氢键也不如与MeCN、MeOH和[ClO(4)]⁻的相应氢键相互作用有利。[Tm(R)]配体的硫原子无法作为有效的氢键受体，这与硫醇盐配体中的硫原子参与形成N-H...S氢键的能力形成显著对比，这一观察结果反映了[Tm(R)]配体的“硫酮”与“硫醇盐”性质。
