Reductive PET cycloreversion of oxetanes: singlet multiplicity, regioselectivity, and detection of olefin radical anion.
Cycloreversion of 2-(p-cyanophenyl)-4-methyl-3-phenyloxetane (1) is achieved using 1-methoxynaphthalene (2) as electron-transfer photosensitizer. The experimental results are consistent with the reaction taking place from the singlet excited state of the sensitizer. Ring splitting of the radical anion 1*- occurs with cleavage of O-C2 and C3-C4 bonds, leading to products (acetaldehyde and p-cyanostilbene) different from the reagents used in the Paterno-Büchi synthesis of 1. The olefin radical anion involved in the electron-transfer process has been detected by means of laser flash photolysis.
Pérez-Ruiz
Raúl
R
Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universidad Politécnica de Valencia, Camino de Vera s/n, Apdo. 22012, 46022 Valencia, Spain.
Izquierdo
M Angeles
MA
Miranda
Miguel A
MA