Structural Effects of Olefins in the Photooxygenation with Electron-Accepting Sensitizers. Kinetic Approach to Reactive Intermediates

Article abstract of DOI:10.1246/cl.1991.1897

Pulsed laser excitation studies on the reactive species in 9-cyanoanthracene(CNA)-sensitized oxygenation of 1,1-diphenyl-2-methylpropene (1a) and (E)-2,3-diphenyl-2-butene (1b) show that the reaction course is mostly governed by competitive quenching of the CNA excited singlet by 1 and oxygen to produce 1^+. and ¹O₂, respectively.The results indicate that the reaction courses of tetraphenylethylene and 2,3-dimethyl-2-butene, for example, can be explaind by exclusive quenching of sensitizer singlets by the olefin and oxygen, respectively.