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