New morpholine‐liganded palladium(II) N‐heterocyclic carbene complexes: Synthesis, characterization, crystal structure, and DNA‐binding studies

Abstract

A series of the morpholine‐liganded palladium(II) complexes (1a–e) bearing N‐heterocyclic carbene (NHC) functionalized by benzonitrile were synthesized. These complexes were synthesized from (NHC)Pd(II)(pyridine) complexes (PEPPSI) and morpholine. The new complexes were fully characterized by using ¹H NMR, ¹³C NMR, Fourier‐transform infrared spectroscopy, and elemental analysis techniques. Single‐crystal X‐ray diffraction was used to determine the structure of a derivative. The DNA‐binding studies of the new (NHC)Pd(II)morpholine complexes were examined using the pBR322 plasmid. The 2,4,6‐trimethylbenzyl derivative compound has the most DNA binding activity. In addition, for the 3‐methylbenzyl derivative compound, oxidation effects were observed at concentrations higher than 100 µg/ml. Also, the molecular and crystal structures of the complex 3‐methylbenzyl derivative compound were recorded by using a single‐crystal X‐ray diffraction method.