Comparative spectral and thermal studies of [Pt(DioxH)2] chelates

• Published in: Journal of coordination chemistry Vol. 62; no. 15; pp. 2429 - 2437
• Main Authors: Várhelyi, Cs, Kovács, A., Gömöry, Á., Pokol, Gy, Farkas, Gy, Sohár, P.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 10.08.2009
• Subjects: Azomethine; Dioxime; Mass spectra; Pt-complexes; Thermoanalytical study
• ISSN: 0095-8972; 1029-0389
• DOI: 10.1080/00958970902852926

Eleven [Pt(DioxH) complexes with various symmetric and asymmetric α-dioximes: R 1 −C(=NOH)−C(=NOH)−R 2 (R 1 = R 2 , R 1 ≠ R 2 , R 1 , R 2 = H, alkyl-, aryl-, alicyclic, heterocyclic groups) are characterized by IR, NMR, and mass spectrometry. The thermal behaviors of these complexes are studied with thermoanalytical methods (TG, DTA, and DSC). The complexes with serial number: 4, 5, 6, 7, and 10 are new compounds. The IR and 1 H NMR-spectra prove the coplanar structure of the [Pt(DioxH) 2 ] complexes stabilized by two very short O-H···O hydrogen bonds. The thermal studies show that the chelates of this type are anhydrous and decompose without well-defined, reproducible melting points. The lack of weight loss and endothermal peaks on the TG and DTA curves, respectively, between 120 and 220°C, proves this phenomenon. The thermal stability of the complexes with symmetrical ligands is higher than with asymmetrical ones. The appearance of the main peaks in the mass spectra (MS) of the complexes shows, generally, an identical decomposition mechanism for all Pt-derivatives studied.