Excited state carbon acids: irreversible photodeprotonation of the benzylic protons of 10-methyl- and 10-phenyl-thioxanthenium salts

Abstract

The first examples of irreversible photodeprotonation of a C–H bond to generate a formal carbanion, via photolysis of thioxanthenium salts, is reported, which gives the corresponding sulfonium ylide (thiaanthracene) and acid (HBF₄ or HClO₄).

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