Development of Cyanopyridazine Derivatives as Photoredox Catalysts and Evaluation of their Catalytic Performance

An array of cyanopyridazine derivatives have been developed through a sequence of (3+3) cycloaddition/oxidative aromatization/derivatization steps. Investigation of the physicochemical properties of these compounds shows that four have interesting fluorescence properties and have the potential to be developed into bimodal photoredox catalysts. One has been confirmed to be an photoredox catalyst in the reactions of N ‐aryl‐ tetrahydroisoquinolines with phosphite, nitromethane, malonitrile and sodium thiocyanate, led to 22%–95% yields. The catalyst capabilities remain with recyclable using under the reaction conditions.