Tetra- and trinuclear platinum(II) cluster complexes

Abstract

Publisher Summary This chapter reviews the chemistry of tetra- and trinuclear platinum(II) cluster complexes. Both clusters are taken as being constructed from a C2v-type PtL4 fragment with two available singly occupied orbitals (isolobal with “CH2”). From this point of view, other new platinum(II) clusters, such as a cyclic pentanuclear cluster or a zigzag chain cluster, could be synthesized. The Pt4 clusters have rich chemistry arising from the lability of the in-plane sites owing to a trans influence (effect) from the Pt–Pt bond. The site-selective lability gives many derivatives of Pt4 clusters and brings catalytic activity to the Pt4 cluster. The Pt4 clusters could be model compounds for metal surfaces as they have two adjacent reaction centers. Furthermore, each Pt in a Pt4 cluster is in the chiral environment, although Pt4 clusters are optically inactive as a whole. It is possible that an effective chiral catalyst will be obtained by choosing an appropriate ligand system. The catalytic activity of Pt3 clusters has not been investigated. They might be more active than Pt4 clusters, because the in-plane ligands in diamine Pt3 clusters dissociate easily in solution whereas those in diamine Pt4 cluster remain intact in solution.