Showing papers by "Milan Melnik published in 2023"

Organomonophosphines in Pt(η3-X1X2X3)(PR3), (X = N1, N2, N3; S1, S2, S3; or Te1, Te2, Te3) Derivatives: Structural Aspects

Abstract: This paper covers nineteen Pt(II) complexes of the composition Pt(η3-X1X2X3)(PR3), (X = N1, N2, N3; S1, S2, S3; or Te1, Te2, Te3). These complexes crystallized in three crystal classes: triclinic (eleven examples), monoclinic (six examples), and orthorhombic (two examples). Each tridentate ligand creates two metallocyclic rings with common N2, S2, or Te2 donor ligands of the types N1C2N2C2N3, N1C2N2NC2N3, S1C2S2C2S3, S1C3S2C3S3, and Te1CNTe2NCTe3. The homotridentate ligand with monodentate PR3 ligand builds up a distorted square planar geometry about Pt(II) atoms. The degree of distortion ranges from 0.029 to 0.092, and the reason for the distortion is discussed. There is an example that contains two crystallographically independent molecules within the same crystal. This is a classic example of distortion isomerism.

Variable Combinations of Tridentate Ligands in Pt(η3-X3L)(PL) Derivatives: Structural Aspects

Abstract: This review covers over fifty Pt(II) monomeric complexes with a wide combination of η3-ligands of the composition Pt(η3-X3L)(PL), (X3 = N3; S3; Te3; ONO; CNC, SeNSe; ONC; ONS; CNS; NNC, NNS; NNSe, SOS; SBS; NON; SSO). The η3-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 τ4 in the following order: 0.023 (6+6) < 0.024 (^+5) < 0.040 (5+6) < 0.062 (5+5).