Novel homoleptic bis-o-semiquinonato nickel complexes

A number of new square-planar bis-(o-semiquinonato) nickel complexes - derivatives of 3,6-di-tert-butyl-o-benzoquinone substituted in 4,5-positions were obtained. Structural features, NIR-IR, 1H NMR spectra and magnetic susceptibility data indicate that complexes properties do not depend dramatically on the electronic properties of substituents in 4,5-position of o-quinone.