Visible-Light-Promoted Catalytic Redox-Neutral Alkynylation of Alkyl Boronic Acids/Boronates

We present a catalytic, redox-neutral strategy for producing internal alkynes through the cross-coupling of alkyl boronic acids and boronates with (hetero)aryl acetylenic bromides. This method proceeds under mild conditions, requires no metal catalysts, and accommodates a wide variety of substrates including medicinally relevant molecules. Mechanistic investigations indicate the in situ formation of a boronate anion complex along with the generation of an alkyl radical under the reaction conditions.我们报道了一种催化、氧化还原中性的策略，通过烷基硼酸与硼酸酯和（杂）芳基炔基溴的交叉偶联反应制备内炔烃。该方法在温和条件下进行，无需金属催化剂，可兼容包括药用相关分子在内的多种底物。机理研究表明，反应过程中会原位生成硼酸酯阴离子络合物，并同时产生烷基自由基。