Cycloaddition of Trifluoroacetaldehyde <i>N</i>-Triftosylhydrazone (TFHZ-Tfs) with Alkynes for Synthesizing 3-Trifluoromethylpyrazoles
Hongwei Wang, Yongquan Ning, Yue Sun, Paramasivam Sivaguru, Xihe Bi
Abstract
-triftosylhydrazone (TFHZ-Tfs) and alkynes is reported. This protocol provides an operationally simple and general method for the synthesis of diverse 3-trifluoromethylpyrazoles in good to excellent yields with broad substrate scope, including aryl, heteroaryl, and alkyl terminal alkynes, and electron-deficient internal alkynes. The synthetic potential of this method was further demonstrated by the synthesis of an antiarthritic drug Celecoxib in multigram scale.
Topics & Concepts
ChemistryCycloadditionArylCombinatorial chemistryAlkylSubstrate (aquarium)Scope (computer science)Organic chemistryCatalysisComputer scienceProgramming languageGeologyOceanographyFluorine in Organic ChemistrySynthesis and Biological EvaluationCyclopropane Reaction Mechanisms