Department of Chemistry, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801, United States.
Org Lett. 2012 Aug 17;14(16):4266-9. doi: 10.1021/ol301570t. Epub 2012 Aug 2.
A method for the synthesis of biaryls and heterobiaryls from arenes and haloarenes without the intermediacy of unstable boronic acids is described. Pinacol boronate esters that are analogous to unstable boronic acids are formed in high yield by iridium-catalyzed C-H borylation of heteroarenes and fluoroarenes. These boronates are stable in the solid state or in solution and can be generated and used in situ. They couple with aryl halides in the presence of simple palladium catalysts, providing a convenient route to biaryl and heteroaryl products that have been challenging to prepare via boronic acids.
本文描述了一种无需使用不稳定硼酸的芳基和卤代芳基合成联芳基和杂联芳基的方法。通过铱催化的杂芳基和氟代芳基的 C-H 硼化反应，高收率地生成了类似于不稳定硼酸的频哪醇硼酸酯。这些硼酸酯在固态或溶液中稳定，可以原位生成和使用。它们在简单钯催化剂的存在下与芳基卤化物偶联，提供了一种方便的途径，可用于制备通过硼酸难以制备的联芳基和杂芳基产物。
