Reactive Oxygen Species (ROS)-vs peroxyl-mediated photosensitized oxidation of triphenylphosphine. A comparative study

S. PROTTI; A. ALBINI; BONESI S. M.

JOURNAL OF ORGANIC CHEMISTRY

AMER CHEMICAL SOC

Lugar: Washington; Año: 2016 vol. 81 p. 11678 - 11685

0022-3263

Abstract. The oxidation of triphenylphosphine in the presence of various photocatalytic systems (dicyanoanthracene/biphenyl, N-methylquinolinium, triphenylpyryliumium and thiatriphenylpyryliumtetrafluoborate) was investigated by means of both steady state and laser flash photolysis experiments. The effect of different additives (including 1,4-benzoquinone, diphenylsulfoxide, tetramethylethilene and sodium azides) on the photosensitized oxidation was investigated in order to fully characterize the involved intermediates. Photoinduced electron transfer and final regeneration of the catalyst occur when dicyanoanthracene and N-methylquinolinium are used, while in cage oxygen transfer to the photoexcited (thio)pyrylium derivatives have been characterized in the last two cases.