Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433 (P. R. China).
Angew Chem Int Ed Engl. 2014 Jul 14;53(29):7624-8. doi: 10.1002/anie.201404543. Epub 2014 Jun 6.
The azo linkage is a prominent chemical motif which has found numerous applications in materials science, pharmaceuticals, and agrochemicals. Described herein is a sustainable heterogeneous-gold-catalyzed synthesis of azo arenes. Available nitroarenes are deoxygenated and linked selectively by the formation of N=N bonds using molecular H2 without any external additives. As a result of a unique and remarkable synergy between the metal and support, a facile surface-mediated condensation of nitroso and hydroxylamine intermediates is enabled, and the desired transformation proceeds in a highly selective manner under mild reaction conditions. The protocol tolerates a large variety of functional groups and offers a general and versatile method for the environmentally friendly synthesis of symmetric or asymmetric aromatic azo compounds.
偶氮键是一种重要的化学结构，在材料科学、制药和农用化学品领域有广泛的应用。本文描述了一种可持续的非均相金催化偶氮芳烃合成方法。可用的硝基芳烃通过分子 H2 脱氧，并选择性地通过 N=N 键形成连接，无需任何外部添加剂。由于金属和载体之间存在独特而显著的协同作用，能够实现硝基亚胺和羟胺中间体的表面介导缩合，在温和的反应条件下，以高选择性的方式进行所需的转化。该方案耐受多种官能团，为环境友好地合成对称或不对称芳香族偶氮化合物提供了一种通用且多功能的方法。
