Photooxygenation of nitrobenzyl derivatives. Mechanisms of photogeneration and hydrolysis of α-hydroperoxy nitrobenzyl ethers

Abstract

The photooxygenation of nitrobenzyl derivatives 1–10 has been studied in aqueous solution as a function of pH. For m-nitrobenzyl ethers 2–4 and 9, stable α-hydroperoxy ethers (11–13) are the primary photochemical products. Acid hydrolysis of 11–13 gives m-nitrobenzaldehyde and hydrogen peroxide. Quantum yields for photooxygenation are reported for a number of derivatives as a function of pH. Acid and base catalyses of photooxygenation are observed for several compounds. A mechanism involving photogenerated nitrobenzyl carbanion intermediates is proposed.