32158-85-3Relevant academic research and scientific papers
Radical Redox-Relay Catalysis: Formal [3+2] Cycloaddition of N-Acylaziridines and Alkenes
Hao, Wei,Wu, Xiangyu,Sun, James Z.,Siu, Juno C.,Macmillan, Samantha N.,Lin, Song
supporting information, p. 12141 - 12144 (2017/09/12)
We report Ti-catalyzed radical formal [3+2] cycloadditions of N-acylaziridines and alkenes. This method provides an efficient approach to the synthesis of pyrrolidines, structural units prevalent in bioactive compounds and organocatalysts, from readily available starting materials. The overall redox-neutral reaction was achieved via a redox-relay mechanism, which harnesses radical intermediates for selective C - N bond cleavage and formation.
Acylated 2,2-dimethylaziridines: Regioselectivity of ring opening by sodium thiophenolate; borderline S(N)2 due to planarization of nitrogen pyramid
Lin,Bellos,Stamm,Onistschenko
, p. 2359 - 2372 (2007/10/02)
2,2-Dimethylaziridines 1 carrying a COR group on nitrogen are opened by PhS(Θ) with a regioselectivity RS = abnormal:normal ≥ 20 in MeOH and 5-16 in THF. Practically no influence of COR on RS was found except for the poorest oxidant 1g (R = tBu) that gave the highest RS (95, MeOH). This rules out an SET mechanism for the abnormal opening. Absence of homolytic ring opening is directly shown by the failure to detect products resulting from cyclization of a homolytically formed radical when COR is cinnamoyl (1f). Direct nucleophilic attack is indicated by suppression of any reaction with PhS(Θ) when the steric hindrance is increased (N-benzoylaziridine 13). The observed S(N)2 borderline behaviour with 1 is explained by reaction in a flattened nitrogen conformation of the otherwise poorly reactive 1. Carboxamide resonance in this (nearly) planar conformation generates a substantial positive charge on N which will shift the mechanism closer to S(N)1 by partial heterolysis of the N-CMe2 bond prior to attack by PhS(Θ).
