Metal-free Sulfontrifluoromethylation And Azidotrifluoromethylation Of Unactivated Alkenes

The CF₃ substituted organic molecules have valuable applications as pharmaceuticals,agrochemicals,materials and can be used in other fields owing to the distinctive physical and biological properties of trifluoromethygroups especially its strong electronegativity,metabolic stability,lipophilicity,and biological toxicity.Based on the difunctionalization strategy of olefin,the preparation is generally limited to three-component reactions using unconventional CF₃precursors and another group precursors.It is of great research significance to develop more efficient and green synthesis methods.Therefore,we have developed a new strategy using trifluoromethanesulfonyl azide and enol triflates as bifunctional reagents for metal-free azidotrifluoromethylation and sulfontrifluoromethylation of unactivated alkenes.The research contents are as follows:(1)Trifluoromethanesulfonyl azide as a bifunctional reagent of alkenes:we developed a method that trifluoromethanesulfonyl azide as a bifunctional reagent to concurrently incorporate both CF₃ and N₃ groups for transition-metal free azidotrifluoromethylation of unactivated alkenes,which provided an atom economic,cost efficient,mild reaction condition and operationally simple method for the synthesis of valuable vicinal difunctionalized structures.The applications were demonstrated by late-stage functionalization of complex bio-important molecules and converting the products into the corresponding CF₃-containing amine,lactam,and other privileged heterocycles.(2)Enol triflates as a bifunctional reagent of alkenes:Base on the previous work,we developed a visible light produced a simple and novel method for the efficient construction of fluoroalkyl-substituted viscous cyclic sulfonyl compounds and fluoroalkyl-substituted spirocyclic sulfonyl compounds using the enol triflate release a CF₃ radical and SO₂ gas from the sulfonyl trifluoromethyl group.