Kumar Naveen, Sharma Navneet, Kumar Vijay, Kumar Vinay, Jangid Kailash, Devi Bharti, Dwivedi Ashish Ranjan, Giri Kousik, Kumar Rakesh, Kumar Vinod
Laboratory of Organic and Medicinal Chemistry, Department of Chemistry, Central University of Punjab Bathinda Punjab India-151401
Department of Computational Sciences, Central University of Punjab Bathinda Punjab India-151401.
RSC Adv. 2024 Feb 19;14(9):6225-6233. doi: 10.1039/d3ra08810c. eCollection 2024 Feb 14.
An efficient metal-free single-step protocol has been developed for the direct synthesis of flavones from 2-hydroxyacetophenone and substituted benzaldehydes. This chemical transformation is exclusively promoted by the iodonium-triiodide ion couple formed through iodine and PEG-400 complexation. The triiodide anion not only helps in the abstraction of a proton from the acetophenone but also promotes the cyclization of intermediate chalcone to the corresponding flavones. The flavones were obtained in very high yields without using any toxic metal catalysts or harsh reaction conditions. The reaction mechanism was established through a series of test reactions and entrapping of reaction intermediates. The developed protocol provides direct access to flavones in high yields under milder reaction conditions with great substrate compatibility, including hydroxylated derivatives.
已开发出一种高效的无金属单步方案，用于从2-羟基苯乙酮和取代苯甲醛直接合成黄酮。这种化学转化仅由通过碘与聚乙二醇-400络合形成的碘鎓-三碘离子对促进。三碘阴离子不仅有助于从苯乙酮中提取质子，还促进中间体查尔酮环化生成相应的黄酮。无需使用任何有毒金属催化剂或苛刻的反应条件，即可获得高产率的黄酮。通过一系列测试反应和捕获反应中间体确定了反应机理。所开发的方案在较温和的反应条件下以高产率直接获得黄酮，具有良好的底物兼容性，包括羟基化衍生物。
