Variable Combinations of Tridentate Ligands in Pt(?(3)-X3L)(PL) Derivatives: Structural Aspects

This review covers over fifty Pt(II) monomeric complexes with a wide combination of ?(3)-ligands of the composition Pt(?(3)-X3L)(PL), (X-3 = N-3; S-3; Te-3; ONO; CNC, SeNSe; ONC; ONS; CNS; NNC, NNS; NNSe, SOS; SBS; NON; SSO). The ?(3)-ligand with monodentate PL displays distorted square-planar geometry about Pt(II) atoms. The structural parameters (Pt-L, L-Pt-L) are analyzed and discussed, with a particular emphasis on the distortion of square-planar geometry about Pt(II) atoms, as well as of the trans-influence. There is a relation between the membered nature of the metallocycles and the distortion of square-planar geometry about the Pt(II) atoms. The distortion increases as indicated by parameter t(4) in the following order: 0.023 (6+6) < 0.024 (<^>+5) < 0.040 (5+6) < 0.062 (5+5).