Study On[2,3]-Sigmatropic Rearrangement Reaction Of New Trifluoromethyl Diazo Reagent(TFHZ-Tfs)

Trifluoromethyl diazomethane?CF₃CHN₂?as a highly reactive,multifunctional trifluoroalkylating reagent has received extensive attention from many researchers in recent years,owing to its widespread use in the trifluoromethylation of a range of organic molecules.However,there is currently only one general method for preparing such a reagent,that is,by reacting sodium nitrite with trifluoroethylamine hydrochloride?CF₃CH₂NH₂·HCl?under acidic conditions.However,existing synthetic strategies typically require manual direct contact with the very dangerous CF₃CHN₂ and the explosive and toxicity nature of the continuously accumulated CF₃CHN₂ during the preparation process also greatly limits the further research and practical industrial application of CF₃CHN₂.In recent years,despite the continuous development of various operating methods of using CF₃CHN₂,the hazardous nature of CF₃CHN₂ still presents a huge potential safety risk.Therefore,it is still a very important task to develop a safer preparation precursor for the multifunctional conversion of trifluoromethyl diazoethane.In this article,we report on a new production strategy that uses trifluoroacetaldehyde N-tfsylhydrazone?TFHZ-Tfs?as a novel precursor for CF₃CHN₂.By safely removed the benzenesulfonyl moiety of the reagent under alkaline heating conditions,this method circumvent the slow addition and manual handling of CF3CHN2 during the course of the actual reaction.In addition,By using new trifluoromethyl diazomethane reagent?TFHZ-Tfs?as a safe precursor for preparation CF₃CHN₂,we achieved a efficient and highly stereoselective metal-carbene transfer reactions,[2,3]-sigmatropic rearrangement reaction,which demonstrate the effectiveness and practicability of this strategy.The development of this method will provide a more secure and efficient production strategy for the continued research of CF₃CHN₂.