SYNTHESIS, STRUCTURE, AND PROPERTIES OF THE ORGANONICKEL σ-COMPLEX [NiBr(Pmp)(bpy)], WHERE Pmp IS 2,3,4,5,6- PENTAMETHYLPHENYL, bpy IS 2,2′-BIPYRIDINE

The organonickel σ-complex 2,3,4,5,6-pentamethylphenyl-nickel(II)-bromide-2,2′-bipyridine is synthesized electrochemically. This is the first example from a series of [NiBr(Aryl)(bpy)] complexes containing a meta- substituted aromatic moiety (Pmp is 2,3,4,5,6-pentamethylphenyl). The obtained compound is characterized in solution by 1 H, 13 С{ 1 H}, and 1 H 13 С{ 1 H}–HSQC NMR and UV spectroscopy and ESI mass spectrometry. The crystal structure is determined by X-ray diffraction. The electrochemical properties of the complex are studied by cyclic voltammetry. It is found that in the DMF solution, a ligand exchange reaction occurs, resulting in the formation of a [Ni(Pmp)(bpy)(DMF)] + derivative with elimination of the bromide anion. Similar cationic derivatives are active in catalytic processes of oligo- and polymerization of olefins, which indicates the importance of data obtained in this work for the development of the chemistry of nickel(II) organometallic complexes.