Di Xiaohui, Garnier Tony, Clerc Arnaud, Jung Eliott, Lherbet Christian, Bénéteau Valérie, Pale Patrick, Chassaing Stefan
Catalyse Organométallique, Synthèse Organique et Santé (COSyS), Institut de Chimie (UMR-CNRS 7177), Université de Strasbourg, 67000 Strasbourg, France.
LSPCMIB, UMR CNRS UPS 5068, Université Toulouse 3 Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse cedex 9, France.
Molecules. 2024 Nov 25;29(23):5552. doi: 10.3390/molecules29235552.
Due to the importance of biaryls as natural products, drugs, agrochemicals, dyes, or organic electronic materials, a green alternative biaryl synthesis has been developed based on easy-to-prepare and cheap copper(I)-exchanged zeolite catalysts. Cu-USY proved to efficiently catalyze the direct homocoupling of either phenols or aryl boronic acids under simple and practical conditions. The Cu-USY-catalyzed oxidative homocoupling of phenols could conveniently be performed under air either in warm methanol or water with good to high yields. In methanol, a small amount of CsCO was required, while none was necessary in water. The homocoupling of aryl boronic acids was best performed also in warm methanol, without an additive. These mild conditions showed good functional-group tolerance, leading to a variety of substituted (hetero)biaryls (28 examples). The heterogeneous Cu-USY catalyst could readily be recovered and reused. Interestingly, the homocoupling of vinyl boronic acids was successfully coupled to a Diels-Alder reaction, even in a one-pot process, allowing access to highly functionalized cyclohexenes.
由于联芳基作为天然产物、药物、农用化学品、染料或有机电子材料的重要性，基于易于制备且廉价的铜（I）交换沸石催化剂，开发了一种绿色的联芳基合成方法。事实证明，Cu-USY能在简单实用的条件下有效催化酚类或芳基硼酸的直接均偶联反应。Cu-USY催化的酚类氧化均偶联反应可以在空气存在下，于温热的甲醇或水中方便地进行，产率良好至高。在甲醇中，需要少量的碳酸铯，而在水中则无需添加。芳基硼酸的均偶联反应同样在温热的甲醇中进行效果最佳，无需添加剂。这些温和的条件显示出良好的官能团耐受性，可得到多种取代的（杂）联芳基（28个实例）。多相Cu-USY催化剂能够轻松回收并重复使用。有趣的是，乙烯基硼酸的均偶联反应甚至可以在一锅法中成功与狄尔斯-阿尔德反应偶联，从而得到高度官能化的环己烯。
