The transition-metal-catalyzed cyanations of aryl halides are among the most used methods for synthesizing aryl nitriles. Despite tremendous advances, cyanating an aryl halide in a facile and benign fashion has generally been unsuccessful. The challenge in this significant transformation is the strong affinity of cyanide for metals, which hampers oxidative addition (OD) and reductive elimination (RE) making organometallic catalysis elusive. Herein, we demonstrate for the first time that photoredox–nickel-catalyzed cyanations of aryl halides are readily enabled by visible light, in which Ni(II) species are transiently oxidized to Ni(III) species, thereby facilitating subsequent cyanide transfer and RE. Using this dual catalysis strategy, we cyanated aryl and alkenyl halides at room temperature in a highly benign manner (30 examples, 53–93% yield) by avoiding the use of air-sensitive ligands, Ni(0) precursors, and hypertoxic cyanation reagents, while also limiting excess metal waste. Computational studies were also used to help understand the present transformation.

芳基卤化物的过渡金属催化氰化是合成芳基腈最常用的方法之一。尽管取得了巨大的进步，但以一种简便和良性的方式氰化芳基卤通常是不成功的。这一重大转变的挑战在于氰化物对金属的强亲和力，这阻碍了氧化加成 (OD) 和还原消除 (RE)，使有机金属催化变得难以捉摸。在此，我们首次证明了芳基卤化物的光氧化还原 - 镍催化氰化很容易通过可见光实现，其中 Ni(II) 物质被瞬时氧化为 Ni(III) 物质，从而促进随后的氰化物转移和 RE。使用这种双催化策略，我们在室温下以高度温和的方式氰化芳基和链烯基卤化物（30 个例子，53–93% 的产率）通过避免使用空气敏感配体、Ni(0) 前体和剧毒氰化试剂，同时还限制了过量的金属废物。计算研究也被用来帮助理解当前的转变。