Regioselective interaction of bifunctional o-quinone, annulated with dithiete cycle, and Ni(CO)4. New heterospin bis(o-semiquinonato) nickel complexes

Abstract Regioselective activation of dioxolene coordination site was observed in reactions of Ni(CO)4 and bifunctional o-quinone, annulated with dithiete cycle (ditQ). Novel hexacoordinated bis(o-semiquinonato) nickel complexes Ni(ditSQ)2(THF)2 (1), Ni(ditSQ)2(Py)2 (2), Ni(ditSQ)2(2,2’-bpy) (3) and Ni(ditSQ)2(4-NIT-Py)2 (4) (4-NIT-Py = 2-(4-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) were obtained. X-ray diffractometry study revealed a distorted octahedral geometry with trans-arrangement of neutral monodentate ligands for Ni ion. Ferromagnetic metal-ligand and antiferromagnetic ligand-ligand exchange interactions were observed in obtained heterospin systems.