Structural characterization of the pyrrole‐2‐carboxaldehydethiosemicarbazonc and its cyclometallathiosemicarbazones with nickel(II), palladium(II), and platinum(II)

Abstract

Abstract The reactions of pyrrole‐2‐carboxaldehyde thiosemicarbazone ( ptsc ) with nickel(II) acetate, K 2 PdCl 4 and K 2 PtCl 4 led to the formation of Ni II ( 1 ), Pd II ( 2 ), and Pt II ( 3 ) metallacycles in which coordination to the metal occurs through the thiocarbonyl sulfur and azomethine nitrogen atoms. The structures of the thiosemicarbazone and the cyclometallated complexes were elucidated by elemental analyses and NMR ( 1 H, 13 C), IR and electronic spectroscopy, and those of ptsc , 1 and 2 were further confirmed by X‐ray diffraction data. Crystal data for ptsc : orthorhombic space group Pbca , a = 22.665(11) Å, b = 9.443(2) Å, c = 7,663(2) Å, Z = 8. Crystal data for 1 : monoclinic space group P 2 1 / n . a = 9.314(3) Å, b = 9.646(3) Å, c = 13.213(4) Å, β = 90.45(3)°, Z = 2. Crystal data for 2 : monoclinic space group P2 1 / n . a = 9.363(1) Å, b = 9,571(1) Å, c = 13.415(1) Å, β = 90.22(1), Z = 2. The structures were solved by direct methods amd were refined to R = 0.058, 0.041 and 0.026 for ptsc , 1 and 2 , respectively.