Aza-Henry/Hemiketamination Tandem Reactions of N-(Benzothiazol-2-yl)imines and 4-nitro-1-phenylbutan-1-one

There being relatively little study on C2 synthons with N-(benzothiazol-2-yl)imines in recent years, the new method study is important for C2 synthons to generate a series of heterocyclic derivatives based on N-(benzothiazol-2-yl)imines. In this paper, a series of N-(hetero)arylpiperidine molecules containing benzothiazole scaffolds were successfully designed and synthesized based on aza-Henry/hemiketamination tandem reaction. An effective method was constructed for synthesizing N-(hetero)arylpiperidine molecules making use of N-(benzothiazol-2-yl)imines and 4-nitro-1-phenylbutan-1-one as the reaction substrates, dichloromethane as the solvent, and potassium phosphate trihydrate (10% mol) as the catalyst at room temperature. Results show that a series of desired products can be obtained in high yield with moderate stereoselectivity, and the tandem reaction still can maintain a better yield and stereoselectivity at the gram-scale.