New Pt(II) Complexes with Heterocyclic Ligands Derived from Benzimidazole: Synthesis, Characterization, DFT Calculations and Catalytic Activities

In this work, the synthesis, spectral characterization, DFT calculations, and catalytic activity of the new Pt(II) complexes with the ligand derived from benzimidazole derivatives have been described. The new heterocyclic ligands were obtained from the reaction of o-amino-ketones with hydrazine hydrate  in  high  yieldandPt(II)  complexes prepared  from  the  coordination  of  the  new ligands  to Pt(II)  cation. The  new  compounds  have  been  characterized  by  spectral  and  microanalytical  data.The DFT  calculations  at the  B3LYP/6-311+G(d,p) level were also  applied to  gain  further insight into the geometry of Pt(II) complexes. The catalytic activity of Pt(II) complexes in Biginellireaction was also examined as heterogeneous catalysts. The results showed that the 3,4-dihydropyrimidin-2(1H)-ones have been synthesized, in excellent yields, under solvent-free conditions, by reaction of tert-butyl acetoacetate, alcohol, arylaldehydes, and urea in the presence of Pt(II) complexes as an efficient and heterogeneous and catalyst.