Protecting groups that can be removed through photochemical electron transfer: mechanistic and product studies on photosensitized release of carboxylates from phenacyl esters

摘要

Photolysis of electron-donating photosensitizers in the presence of virous phenacyl esters (PhCOCH_2OCOR) results in C-O bond scission leding to the formation of acetophenone (PhCOCH_3) and the corresponding carboxylic acid (RCO_2H). Prepartive experiments showed that the carboxylic acids are generated in high or quantitative isolated yields. It is argued that this reaction is initiated by a photoinduced electron transfer from the excited state sensitizer to the phenacyl ester.