Laboratório de Síntese Orgânica Limpa - LASOL, CCQFA, Universidade Federal de Pelotas - UFPel, P.O. Box 354 - 96010-900 Pelotas, RS. Brazil.
Laboratory of Biotechnology of Natural and Synthetic Products, Universidade de Caxias do Sul, 95070-560 Caxias do Sul, RS, Brazil.
J Org Chem. 2021 Oct 15;86(20):14016-14027. doi: 10.1021/acs.joc.1c00271. Epub 2021 Mar 22.
A new method was developed for the synthesis of 4-chalcogenyl-1-isochromen-1-ones through the 6-- electrophilic cyclization of 2-alkynylaryl esters and diorganyl dichalcogenides under ultrasound irradiation. The reactions were performed under mild conditions, using Oxone as a green oxidant to promote the cleavage of the chalcogen-chalcogen bond in diorganyl diselenides and ditellurides to generate electrophilic species . A total of 25 compounds were selectively obtained after 30-70 min, in good to excellent yields (74-95%). This procedure was extended to prepare 5-selenopheno[3,2-]isochromen-5-ones. Additionally, for the first time, the 4-chalcogenyl-1-isochromen-1-ones were used as substrates in the thionation reaction, using Lawesson's reagent and microwave irradiation under solvent-free conditions, obtaining the thio derivatives in yields of up to 99% in only 15 min.
通过超声辐射下 2-炔基芳基酯和二有机二硒化物和二碲化物的 6--亲电环化，开发了一种合成 4-硫代/硒代-1-异苯并呋喃-1-酮的新方法。该反应在温和条件下进行，使用 Oxone 作为绿色氧化剂促进二有机二硒化物和二碲化物中二硒/碲键的断裂，生成亲电物种。在 30-70 分钟后，总共选择性地获得了 25 种化合物，产率为 74-95%。该方法扩展到制备 5-硒代苯并[3,2-]异苯并呋喃-5-酮。此外，首次使用 4-硫代/硒代-1-异苯并呋喃-1-酮作为底物，在无溶剂条件下使用劳森试剂和微波辐射进行硫代反应，仅在 15 分钟内获得高达 99%的硫代衍生物产率。
