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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Photocatalytic [4 + 1] Annulation of Vinyl Aziridines with Alkyl Halides
Dan Wang1, Xintao Liu1, Jinghan Zhang1
1College of Chemistry and Molecular Sciences, Henan University, Kaifeng 475004, P. R. China.
Abstract:
Herein, we develop a photocatalytic [4 + 1] annulation of vinyl aziridines with alkyl halides. The reaction appears to experience radical trigger kinetically favored β-scission of the vinyl aziridine C-N bond, generating transient nitrogen-centered radical, followed by sequential single electron oxidation, 5-exo-trig cyclization, and protonation. Significantly, an unprecedented annulation mode in which vinyl aziridines serve as four-atom synthons has been disclosed.
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