Synthesis Of Pyrazolines And Oxidative Coupling Reactions Of Trifluoromethyled Acylhydrazones

Pyrazolines are important five-membered nitrogen-containing heterocyclic compound.Various pyrazoline derivatives can be synthesized by condensation reaction,cycloaddition reaction and intramolecular cyclization reaction.The synthesis of pyrazoline compounds from ?,?-unsaturated hydrazone compounds by photocatalysis reaction,radical cyclization,metal catalysis reaction and halogenation cyclization has been research hotspots in the past five years.Based on a brief review of the synthesis and application of pyrazoline derivatives,the cascade oxidation/halogenoaminocyclization reaction of homoallylhydrazides promoted by NIS was explored.In addition,the oxidation/coupling reaction of trifluoromethylhydrazones and amines was studied preliminarily by using trifluoromethylhydrazone as trifluoromethyl synthetic block.The thesis mainly consists of the following three parts:Chapter one: Reserch Progress in the application and synthesis of PyrazolinesIn this chapter,the application of pyrazoline in the fields of pharmacy,pesticides,material science have been summarized.Then we mainly descrided the methods of synthesis of pyrazolines from hydrazines,diazoacetates,hydrazones and unsaturated hydrazones.Chapter two: Synthesis of Pyrazolines by Cascade Oxidation/Halogenoaminocyclization Reaction of HomoallylhydrazidesAn efficient oxidative halocyclization of homoallylhydrazides with N-halogensuccinimide was developed to provide facile access to pyrazolines.The reaction have following advantages: mild reaction conditions,without any other additive and high reaction yield.The protocol provides an efficient synthesis strategy for the construction of pyrazolines,which have potential biological activity.Chapter three: The Oxidative Coupling Reactions of Trifluoromethyl Acylhydrazones and Amines.This chapter explores the oxidative coupling reaction of trifluoromethyl acylhydrazones and amines by I2 and TBHP promotion.The amination reaction of trifluoromethyl acylhydrazones is successfully studied,which avoids further expands the applicaton of trifluoromethyl acylhydrazones in organic synthesis...