Teja Chitrala, Nawaz Khan Fazlur Rahman
Organic and Medicinal Chemistry Research Laboratory, School of Advanced Sciences, Vellore Institute of Technology. Vellore 632014, Tamil Nadu India.
Org Lett. 2020 Mar 6;22(5):1726-1730. doi: 10.1021/acs.orglett.9b04598. Epub 2020 Feb 14.
An efficient, solvent-free synthesis of 2-acylthieno[2,3-]quinolines is reported from 2-halo-quinolinyl ketones through Cu-TEMPO catalyzed dehydrogenation, sp-C-H functionalization using elemental sulfur as thiol surrogate (sulfur source) and tetrabutylammonium acetate as an ionic reaction medium. The optimized reaction conditions give excellent product yields under mild reaction conditions with chemoselectivity and broad functional group tolerance. The synthetic importance of the synthesized molecules is showcased further by Friedländer annulation, reduction, and alkene functionalization reactions.
报道了一种从2-卤代喹啉基酮出发，通过铜-四甲基哌啶氮氧化物（Cu-TEMPO）催化脱氢、以元素硫作为硫醇替代物（硫源）以及乙酸四丁铵作为离子反应介质进行sp-C-H官能化，实现2-酰基噻吩并[2,3-b]喹啉的高效无溶剂合成。优化后的反应条件在温和反应条件下能给出优异的产物收率，具有化学选择性和广泛的官能团耐受性。通过Friedländer缩合、还原和烯烃官能化反应进一步展示了所合成分子的合成重要性。
