Retro-cyanohydrination

More recently, Jin et al. discovered an efficient copper-catalyzed cyanation of arenes 119 nsing benzyl nitrile as a cyanide anion surrogate, which fiunishes aromatic nitriles 120 (Scheme 5.84) [85]. The process involves at least three steps, where (1) benzyl nitrile undergoes a copper-catalyzed oxidation with air to generate A and B, accompanied by the generation of Cu(II) species (2) cyanide anion is formed throngh a retro-cyanohydrination of A or/and hydrolysis of B and (3) the in situ-generated cyanide anion participates in the copper(II)-catalyzed aerobic oxidative C—H fnnctionalization to afford the cyanation product. 

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