Development of a Robust Protocol for the Synthesis of 6-Hydroxybenzofuran-3-carboxylic Acid
作者:Isabelle Gallou、Bernhard Erb、Michael Marti、Gian-Luca Nuzzo、Andreas Jager、Manuela Seeger、Pierre Chassagne、Jonas Aronow、Margery Cortes-Clerget、Fabrice Gallou
DOI:10.1021/acs.oprd.9b00546
日期:2020.5.15
Benzofuran scaffolds are fundamental moieties found in a variety of biologically active natural products and synthetic drugs. In the course of one of our development programs, we needed to develop a practical and cost-effective manufacturing approach to such a benzofuran scaffold. Here we report a highly robust four-step, one-pot process that provides access to a 6-hydroxybenzofuran-3-carboxylic acid structure. An H-1 NMR monitoring study allowed a better understanding of the overall sequence of events and the nature of the detected intermediates. After six steps, including the optimized tandem process, the desired hydroxylated benzofuran was obtained in 40% yield with a purity above 99%.