Photochemical Asymmetric Nickel-Catalyzed Acyl Cross-Coupling
Photochemical Asymmetric Nickel-Catalyzed Acyl Cross-Coupling
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DOI：
10.1002/anie.201910168
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发表时间：
2019-10-07
影响因子：
16.6
通讯作者：
Melchiorre, Paolo
中科院分区：
文献类型：
--
作者：
Gandolfo, Eugenio;Tang, Xinjun;Melchiorre, Paolo
光化学对映选择性镍催化的交叉偶联反应很难实现。我们报道了一种可见光介导的策略，成功地偶联对称酸酐和4-烷基二氢吡啶（DHPs）在温和条件下提供对映体富集α -取代酮。这种化学反应不需要外源性光催化剂。它是由DHPs的直接激发引发的，DHPs作为自由基源和还原剂，促进手性催化镍配合物的周转。
Photochemical enantioselective nickel-catalyzed cross-coupling reactions are difficult to implement. We report a visible-light-mediated strategy that successfully couples symmetrical anhydrides and 4-alkyl dihydropyridines (DHPs) to afford enantioenriched alpha-substituted ketones under mild conditions. The chemistry does not require exogenous photocatalysts. It is triggered by the direct excitation of DHPs, which act as a radical source and as a reductant, facilitating the turnover of the chiral catalytic nickel complex.