Nickel(II) Complex with the Bis(phenolate) Pincer N-Heterocyclic Carbene Ligand: Synthesis, Structure, and Properties

The nickel(II) complex Ni(L)Py (I) (L is 1,3-bis(3,5-di-tert-butyl-2-phenolato)-5,5-dimethyl-(4,6-dihydropyrimidin-2-ylidene)) containing the dianionic bonded N-heterocyclic carbene (NHC) bis(phenolate) ligand is synthesized. In the presence of a stronger base (4-dimethylaminopyridine (DMAP)), the exchange reaction occurs with the replacement of pyridine in complex I by the DMAP molecule to form complex Ni(L)(DMAP) (II), the crystal structure of which is determined by XRD. The synthesized compounds are characterized by elemental analysis, mass spectrometry, and NMR spectroscopy. The spectral characteristics of the compounds are studied.