College of Materials Science & Engineering, Huaqiao University , Xiamen 361021, China.
Engineering Research Center of Molecular Medicine, Ministry of Education, Key Laboratory of Molecular Medicine of Fujian Province, Key Laboratory of Xiamen Marine and Gene Drugs, Institutes of Molecular Medicine and School of Biomedical Sciences, Huaqiao University , Xiamen 361021, China.
J Org Chem. 2017 Sep 15;82(18):9515-9524. doi: 10.1021/acs.joc.7b01541. Epub 2017 Sep 1.
An efficient cascade reaction via trapping in situ generated active intermediate 1,4-oxazepine, formed from base-promoted 7-exo-dig cyclization reaction of N-propargyl enaminone, has been developed. Alcohols/thiols and aldehydes were used as trapping agents, providing 2-alkoxy/2-sulfenylpyridines and dihydrofuro[2,3-b]pyridines in moderate to high yields. This cascade reaction was completed within 30 min at room temperature, generating 1 equiv of HO as the sole byproduct.
通过将原位生成的活性中间体 1,4-恶嗪捕捉到反应中，实现了一种高效的级联反应。该中间体是由 N-炔丙基烯胺酮的碱促进的 7-endo-dig 环化反应形成的。醇/硫醇和醛作为捕获剂，提供了中等至高产率的 2-烷氧基/2-硫基吡啶和二氢呋喃并[2,3-b]吡啶。该级联反应在室温下 30 分钟内完成，仅生成 1 当量的 HO 作为唯一的副产物。
