Visible Light Promoted Synthesis of 3-Sulphonyl Coumarins from Alkyoates
Coumarins are a key class of heterocyclic lactone compounds,which have good biological activity.3-sulfonyl coumarin derivatives were prepared by visible light promoted reaction of benzoalkynyl esters with sodium benzenesulfonate,and their reaction mechanism was studied.The results showed that under mild reaction conditions,3-sulfonyl coumarin derivatives can be synthesized with moderate to good yields using sodium benzenesulfite as the precursor of sulfonyl radicals and persulfate as the oxidant through a cascade radical addition cyclization strategy,providing a concise,green,and efficient synthetic route for the preparation of functionalized coumarin derivatives.