Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, N-9037 Tromsø, Norway.
Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark.
Org Biomol Chem. 2020 Mar 4;18(9):1754-1759. doi: 10.1039/d0ob00044b.
We have developed a carbonylative approach to the synthesis of diversely substituted 2-aroylbenzoate esters featuring a new protocol for the carbonylative coupling of aryl bromides with boronic acids and a new strategy to favour carbonylative over non-carbonylative reactions. Two different synthetic pathways - (i) the alkoxycarbonylation of 2-bromo benzophenones and (ii) the carbonylative Suzuki-Miyaura coupling of 2-bromobenzoate esters - were evaluated. The latter approach provided a broader substrate tolerance, and thus was the preferred pathway. We observed that 2-substituted aryl bromides were challenging substrates for carbonylative chemistry favouring the non-carbonylative pathway. However, we found that carbonylative Suzuki-Miyaura couplings can be improved by slow addition of the boronic acid, suppressing the unwanted direct Suzuki coupling and, thus increasing the yield of the carbonylative reaction.
我们开发了一种羰基化方法，用于合成各种取代的 2-芳酰基苯甲酸酯，其中包括一种新的芳基溴与硼酸的羰基化偶联反应的方案，以及一种有利于羰基化反应而不是非羰基化反应的新策略。评估了两种不同的合成途径：（i）2-溴二苯甲酮的烷氧基羰基化，以及（ii）2-溴苯甲酸酯的羰基化铃木-宫浦偶联。后一种方法提供了更广泛的底物耐受性，因此是首选途径。我们观察到，2-取代的芳基溴是羰基化化学的挑战性底物，有利于非羰基化途径。然而，我们发现，通过缓慢添加硼酸，可以改善羰基化铃木-宫浦偶联，抑制不必要的直接铃木偶联，从而提高羰基化反应的产率。
