Synthesis, Structures, and Catalytic Properties of Ionic Metallacyclodimeric Palladium(II) Complexes

Abstract

Metallacyclodimeric complexes of [(Me 4 en)Pd(L)] 2 (ClO 4 ) 4 (Me 4 en = N,N,N',N'-tetramethylethylenediamine; L = dimethylbis(4-pyridyl)silane (dmps), methylvinylbis(4-pyridyl)silane (mvps)) have been synthesized, and their structures have been characterized by X-ray single crystallography. The skeletal structures consist of one 20-membered metallamacrocycle, two 5-membered metallacycles, and four pyridyl groups. The local geometry around the palladium(II) ion approximates to a typical square planar arrangement with four nitrogen donors. Delicate difference in catalytic effects on hydrogenation was investigated based on the structure of catalyst and substrates.