Synthesis and structure of the new heteronuclear palladium-mercury cluster

Abstract

Interaction of the tetra-nuclear phosphinecarbonyl complex of zero-valent palladium, Pd4(CO)5(PEt3)4 (I), with a four-fold excess of 8-(α-bromomercuryethyl)quinoline gives a new neutral heteronuclear cluster Pd4Hg2Br2(CO)4(PEt3)4 (IV). The structure of (IV) was determined by an X-ray analysis. The molecule of (IV) contains a “butterfly” Pd4(μ2-CO)4(PEt3)4 moiety, whose triangular “wings” are capped by Hg atoms bonded also to bromo-ligands. The metal Hg2Pd4 polyhedron consists of two heteroatomic Pd3Hg tetrahedra with a common PdPd edge. The IR- and 31P-NMR spectra of (IV) were also studied.