Lunic Danijela, Sanosa Nil, Funes-Ardoiz Ignacio, Teskey Christopher J
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
Department of Chemistry, Centro de Investigación en Síntesis Química (CISQ), Universidad de La Rioja, Madre de Dios 53, 26006, Logroño, Spain.
Angew Chem Int Ed Engl. 2022 Oct 24;61(43):e202207647. doi: 10.1002/anie.202207647. Epub 2022 Sep 21.
Although considerable advances have been made in developing chemoselective transformations of ubiquitous carboxylic acid groups, many challenges still exist. For instance, their selective reduction is problematic if both more nucleophilic and more electrophilic groups are present in the starting material. Here, we address this problem with a simple and mild protocol using bench-stable reagents at ambient temperatures. This platform is able to tolerate a diverse range of functionality, leaving ketones, esters, nitro-groups, olefins, nitriles and amides untouched. A combination of experimental and computational mechanistic experiments demonstrate that this reaction proceeds via hidden borane catalysis with small quantities of in situ generated BH playing a key role in the exquisite selectivity that is observed.
尽管在开发普遍存在的羧酸基团的化学选择性转化方面已经取得了相当大的进展，但仍然存在许多挑战。例如，如果起始原料中同时存在亲核性更强和亲电性更强的基团，它们的选择性还原就会出现问题。在这里，我们通过在室温下使用稳定的试剂的简单温和方案解决了这个问题。该平台能够耐受多种官能团，使酮、酯、硝基、烯烃、腈和酰胺不受影响。实验和计算机理实验相结合表明，该反应通过隐藏的硼烷催化进行，少量原位生成的BH在所观察到的优异选择性中起关键作用。
