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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Cycloreversion of β-lactams via photoinduced electron transfer
Raúl Pérez-Ruiz1, Jose A Sáez, M Consuelo Jiménez
1Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politécnica de València, Camino de Vera s/n, 46022, Valencia, Spain. mcjimene@qim.upv.es mmiranda@qim.upv.es.
Abstract:
The radical anions of β-lactams, photogenerated in the presence of DABCO as an electron donor, undergo cycloreversion via N-C4 bond cleavage, back electron transfer and final C2-C3 bond cleavage, leading to olefins. The involved intermediates are 1,4-radical anions and 1,4-biradicals. The experimental observations are consistent with the results of DFT calculations.
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