Photo-induced thiol coupling and C–H activation using nanocrystalline lead-halide perovskite catalysts†
The use of photon energy to promote chemical transformations offers versatile control of reaction kinetics and progress. Over the past decade, many photoactive transition-metal complexes and organic chromophores were developed to catalyze chemical transformations, enabling a myriad of reactions and compounds that were previously inaccessible via traditional synthetic methods. Here, we demonstrate the photocatalytic oxidative coupling of organic thiols using cesium lead halide perovskite nanocrystals as photocatalysts. The photo-catalyzed thiol coupling reactions selectively produced symmetric and unsymmetrical disulfides in high yields (68–96% isolated yields). Additionally, we discovered a perovskite-catalyzed phosphonylation of tertiary amines via visible-light-mediated cross-dehydrogenative coupling reaction, and obtained good isolated yields (50–96%). The variety of visible-light-induced photocatalytic processes that perovskite nanocrystals are capable of, coupled with their facile preparation, easily tunable redox potentials, high catalytic efficiency and reusability, presents great opportunities for their future applications in green and sustainable organic synthesis.