2-Mercapto-1-t-butylimidazolyl as a bridging ligand: Synthesis and structural characterization of nickel and palladium paddlewheel complexes

Nickel and palladium paddlewheel complexes that feature 2-mercapto-1-t -butylimidazolyl (mimButmimBut) bridging ligands, namely Ni2[mimButmimBut]4 and Pd2[mimButmimBut]4, have been synthesized and structurally characterized by X-ray diffraction. Since the mimButmimBut ligand bridges in an asymmetric manner via a sulfur and nitrogen donor, paddlewheel compounds of the type M2[mimButmimBut]4 may exist as isomers that are distinguished by the relative orientations of the ligands. In this regard, the (4,0)-Ni2[mimButmimBut]4 and trans -(2,2)-Ni2[mimButmimBut]4 isomers have been isolated for the nickel system, while the (4,0)-Pd2[mimButmimBut]4 and (3,1)-Pd2[mimButmimBut]4 isomers have been isolated for the palladium system.