作者:Zheng-Hai Wang、Dong-Hui Wang
DOI:10.1021/acs.orglett.1c04322
日期:2022.1.21
A Cu-catalyzed straightforward synthesis of benzoxazoles from free phenols and cyclic oxime esters is reported. The mild reaction conditions tolerate various electron-withdrawing and electron-donating functional groups on both substrates, affording benzoxazoles in moderate to good yields. With this protocol, large-scale syntheses of Ezutromid and Flunoxaprofe in one or two steps are demonstrated. A
报道了一种由游离酚和环肟酯催化直接合成苯并恶唑的方法。温和的反应条件耐受两种底物上的各种吸电子和给电子官能团,以中等至良好的产率提供苯并恶唑。使用该协议,证明了在一个或两个步骤中大规模合成Ezutromid和Flunoxaprofe 。提出了一种催化机制,包括通过内球电子转移和随后的环化进行铜催化胺化。