Department of Chemistry, National Institute of Technology Warangal, Warangal, Telangana 506004, India.
J Org Chem. 2022 Aug 5;87(15):9915-9925. doi: 10.1021/acs.joc.2c00936. Epub 2022 Jul 15.
A transition metal- and hydride-free protocol has been developed for the chemoselective reduction of α-keto esters and α-keto amides using rongalite as a reducing agent. Here, rongalite acts as a hydride-free reducing agent a radical mechanism. This protocol offers the synthesis of a wide range of α-hydroxy esters and α-hydroxy amides with 85-98% yields. This chemoselective method is compatible with other reducible functionalities such as halides, alkenes, amides, and nitriles. The use of inexpensive rongalite ( $0.03/1 g), mild reaction conditions, and gram-scale synthesis are some of the key features of this methodology. Also, cyclandelate, a vasodilator drug, has been synthesized in gram scale with 79% yield.
已开发出一种无过渡金属和氢化物的方法，使用吊白块作为还原剂，对α-酮酯和α-酮酰胺进行选择性还原。在此，吊白块充当无氢化物还原剂，遵循自由基机理。该方案可用于合成范围广泛的α-羟基酯和α-羟基酰胺，产率为 85-98%。这种选择性方法与其他可还原官能团如卤化物、烯烃、酰胺和腈相容。使用廉价的吊白块（$0.03/1 g）、温和的反应条件和克级规模的合成是该方法的一些关键特征。此外，以 79%的产率用克级规模合成了血管扩张药物环扁桃酯。
