Synthesis of Selenenium Ions: Isolation of Highly Conjugated, pH-Sensitive 4,4′-Bis(methylimino)-1,1′-binaphthylene-5-diselenenium(II) Triflate

The isolation of novel selenenium cations, stabilized by only one intramolecularly coordinating group (Se···N), is described. The electronic nature of the cations has been probed by calculating natural bonding orbital charges and Wiberg bond indices. [8-(Dimethylamino)-1-naphthyl]selenenyl(II) triflate oxidizes in methanol via C–C coupling to give a novel blue-colored 4,4′-bis(methylimino)-1,1′-binaphthylene-5-diselenenium(II) triflate. The pH dependence of the color has been investigated.