Synthesis Of N-Heterocycles Based On Ketenimines And Aziridines

The synthesis of heterocyclic compounds is central issue in organic chemistry, as one of the most popular kinds of heterocyclic compounds,N-eterocycles are widely used in biology, pharmaceutical chemistry and material. It’s also challenging work to develop new methods and find new mechanisms in the synthesis of heterocyclic compounds. Previous work of reactions participated by ketenimines and aziridines were summarized, some reactions were developed to synthesize.N-heterocycles based on ketenimines and aziridines. The main content showed below:1. Three-Component Reaction of Propargyl Amines, Sulfonyl Azides, and Alkynes: One-Pot Synthesis of Tetrasubstituted ImidazolesThree-Component Reaction of Propargyl Amines, Sulfonyl Azides, and Alkynes were developed, N-Sulfonyl Ketenimine formed first, which was captured by propargyl amine, the propargyl amine transformed to aminoallene, after a6π-ECR and a sulfonyl1,3-shift, the product formed.2. Two-Component Reaction of Propargyl Amines, Ketenimines:Synthesis of ImidazolesThis kind of Ketenimines could be separated, propargyl amine attacked the ketenimine first, then the triple bond was activated by metal Lewis Acid, the product was formed after aromatization.3. Diasteroselective Synthesis of Oxazolidines and Imidazolidines via the [3+2] Cycloaddition of AziridinesTwo ester groups were added to aziridine, so its C-C bond cleavaged to participate the [3+2] cycloaddition with aromatic aldehydes and imines. The reactions were highly diastereoselective to form c7.s-2,5-disubstitutedoxazolidines and lrans-2,5-disubstitutedimidazolines. All the reactions above were with good yield, simple conditions, high atom economy and high diastereoselective.