A new pathway was developed for the synthesis of benzyl benzoates via TBAI-mediated oxidative self-coupling of benzyl bromides in the presence of tert-butyl hydroperoxide (TBHP) as an oxidant under solvent-free conditions. Various derivatives of precursors
including electron donating and withdrawing groups as well as heteroaromatic and polycyclic benzyl bromides were subjected to the reaction conditions and converted to the corresponding benzylic esters in good to high yields. Mechanistic studies showed that this reaction did not take place via the radical pathway and tert-butyl peresters and benzoic acids are two key intermediates in this transformation.
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