Study On The Reaction Of Three-component Synthesis Of Amidine Compounds

As a prominent nitrogen-containing structural motif,amidines are ubiquitous in bioactive natural products,pharmaceuticals compounds,super bases,and nucleophilic catalysts.Furthemore,they serve as agrochemicals and synthetic precursors in organic synthesis.With the increasing use of amidine compounds,the development of efficient methods for the diversity oriented amidine synthesis has attracted intense attentions.Multicomponent reaction?MCR?is an important strategy to efficiently access highly functionalized structure motifs with its benefit of step economy and atomic economy.Herein we report a mild,transition-metal-free three-component reaction for N-acyl amidine synthesis from trans-?-nitrostyrene derivatives,tert-butyl dibromocarbamate?BocNBr₂?and amines.The key steps involved in the process of multi-component synthesis of the compounds are optimized.Firstly,we synthesized nitrostyrene derivatives.BocNBr₂ was synthesized from tert-butyl carbamate.Subsequently,the key steps involved in the synthesis of amidine compounds are optimized.The optimum reaction conditions were obtained,and the optimal reaction conditions were used to synthesize 42 kinds of amidines.It includes amidine structure and?,?-unsaturated amidine structure which are difficult to be prepared.Three amidine compounds were synthesized by a one-pot manner,including amidines protected by acetyl,benzoyl and benzyl oxo carbonyl groups.Through a series of control experiments,the mechanism of the reaction mechanism was speculated and analyzed.And the structures were characterized by high-resolution mass spectrometry,melting point,X-ray,¹H NMR and¹³C NMR.