Department of Energy Systems Research, Ajou University, Suwon 16499, Korea.
J Org Chem. 2022 Apr 1;87(7):4631-4639. doi: 10.1021/acs.joc.1c02981. Epub 2022 Mar 16.
Ir(NHC) (NHC, -heterocyclic carbene)-catalyzed dehydrogenative coupling of sustainable ethylene glycol and various bioalcohols can produce industrially valuable α-hydroxy acids (AHAs). This study is the first to report the sustainable synthesis of higher C AHAs, in addition to glycolic acid (C AHA) and lactic acid (C AHA). This catalytic system can be recycled to the seventh cycle while maintaining good yields. A reaction mechanism, including facile dehydrogenation of each alcohol and fast cross-coupling of dehydrogenated aldehydes forming products, was proposed based on O- and H-labeling experiments and electron spray ionization-mass spectrometry (ESI-MS) and NMR spectral analyses.
铱（NHC）（NHC，杂环卡宾）催化可持续的乙二醇和各种生物醇的脱氢偶联可以生产具有工业价值的α-羟基酸（AHAs）。本研究首次报道了可持续合成更高 C 的 AHAs，除了乙醇酸（C AHA）和乳酸（C AHA）。该催化体系可循环使用七次，同时保持良好的收率。通过 O-和 H-标记实验以及电子喷雾电离质谱（ESI-MS）和 NMR 光谱分析，提出了一种反应机理，包括每个醇的易脱氢和脱氢醛的快速交叉偶联形成产物。
