Structure and physical properties of several pseudotetrahedral zinc complexes containing a new alkyl thiolate heteroscorpionate ligand

摘要

A series of pseudotetrahedral and octahedral zinc(II) complexes of the heteroscorpionate ligand bis(3,5-dimethyl-pyrazoly)(1-methyl-1-sulfanylethyl)methane (L3SH) have been synthesized and most characterized by X-ray crystallography. pseudotetrahedral complexes isolated include [Zn(L3S)(CH_3)], [Zn(L3S)(Cl)], [Zn(L3S)(OAc)], [Zn(L3S)(SPh~(F5))], [Zn(L3S)(SBz)] (Bz = CH_2Ph), [Zn(L3S)(OPh~(p-NO_2))], and [Zn(L3S)_2]. In addition, the octahedral complex [Zn{(L3S)_2Zn}{O_2P(OPh)_2}_4] was also synthesized. comparisons between these complexes and those of the corresponding tris(pyrazolyl)borate, Tp~-, or aromatic phenol or benzenethiolate ligands (L1O)~- and (L2S)~- reveal significant differences. Among these is a change in binding of acetate from pure unidentate to anisobidentate as the ligand donor is changed from S to N to O. Trends such as these may aid in understanding how the donor wet affects the structure and reactivity at pseudotetrahedral zinc centers in metallopropteins.