LAUSR

Abstract Reaction of 2-((2-(phenylthio)phenyl)amino)-4-((2-(phenylthio)phenyl)imino)naphthalene-1(4H)-one (LH2) that is a N,S-chelating 1,4-iminonaphthoquinone derivative, with [Pd(DMSO)2Cl2] in boiling MeOH promotes an aromatic C H activation reaction affording an orthopalladated iminonaphthoquinone derivative, [PdII(LH−)Cl] (1). The molecular geometries and the bond parameters of LH2 and 1 were confirmed by single crystal X-ray crystallography. The redox activity of 1 is notably different from LH2. The 1/1 − and 1 −/12− redox couples are reversible due to successive reduction of LH− to 1,4-iminonapthasemiquinone anion radical (LH 2−) and 1,4-imidonaphtholate (LH3−), while the LH2/ LH2 − redox couple is irreversible. 1 − exhibits an EPR signal at g = 2.002 and the spin density obtained from the unrestricted B3LYP/DFT calculation is localized on the 1,4-iminoquinone fragment. The UV–vis-NIR absorption spectrum of 1 − recorded by a spectroelectrochemical measurement displays a characteristic NIR band at 800 nm that is absent in 1 and 12−.