Bi(OTf)₃-[Bmim]PF₆:A novel and Reusable Catalytic System for the Synthesis ofcis -AziridineCarboxylates

Abstract

Aldimines (generated in situ from aldehydes and amines) react readily with ethyl diazoacetate in the presence of 2 mol% of Bi(OTf) 3 or 5 mol% of Sc(OTf) 3 in [bmim]PF 6 ionic liquid to produce the corresponding aryl aziridine carboxylates in high yields with excellent cis-diastereoselectivity. The recovered ionic liquid containing catalyst was reused in three to four subsequent runs with gradual decrease in activity.

Dimensional Reduction of Lewis Acidic Metal–Organic Frameworks for Multicomponent Reactions

“…At 1.0 mol % loading of Zr 6 OTf-BTB, a mixture of aniline, benzaldehyde, and ethyl diazoacetate was quantitatively converted to cis -ethyl 1,3-diphenylaziridine-2-carboxylate ( 20 ) at room temperature in 6 h. Such aziridine derivatives can be further elaborated into useful nitrogen-containing molecules. Zr 6 OTf-BTB also significantly outperformed traditional homogeneous Lewis acidic catalysts, which typically required much higher catalyst loadings (10–20 mol %), in this MCR. − More importantly, by varying the substrate components with different anilines, aldehydes, and diazo reagents, we successfully synthesized a series of aziridine carboxylates in good to outstanding yields (66–94%) with excellent cis selectivity and good functional group tolerance (Table ).…”

3-Arylaziridine-2-carboxylic Acid Derivatives and (3-Arylaziridin-2-yl)ketones: The Aziridination Approaches

“…The yields of aziridines cis-1a in both studies exceeded 80%. Ten [45] and twelve [46] examples were demonstrated, respectively.…”

“…Ionic liquids have been successfully tested for cis-selective AZ reactions [45,46]. Reactions of aromatic aldimines were carried out in bmim PF 6 at room temperature [45] and in the same liquids in multi-component variation with 2 mol% of Bi(OTf) 3 or 5 mol% of Sc(OTf) 3 catalyst [46] addition. The yields of aziridines cis-1a in both studies exceeded 80%.…”

[Bmim]PF6: An efficient tool for the synthesis of diverse bioactive heterocycles

“…In the same year, another method was reported for the synthesis of cis-diastereoselective aryl aziridines (3) via three-component reactions of aldehydes (4), various amines (5) and ethyl diazoacetate (2) using Bi(OTf) 3 or Sc(OTf) 3 as catalyst in the same ionic liquid at 27 °C (Scheme 2). 54 The use of a catalyst red-________________________________________________________________________________________________________________________ (CC) 2018 SCS.…”