Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
Org Lett. 2023 Apr 7;25(13):2258-2263. doi: 10.1021/acs.orglett.3c00509. Epub 2023 Mar 26.
An operationally simple and efficient domino etiquette has been developed for the facile construction of 1,2-dithioles employing easily accessible dithioesters as a three-atom CCS synthon and aryl isothiocyanates as a two-atom CS unit in the absence of any catalyst and additive at room temperature under open air. The reaction proceeded efficiently affording the desired 1,2-dithioles in good yields having various functional groups of a diverse electronic and steric nature. This approach avoids possible toxicity and tiresome workup conditions and features easy to handle, cheap, and readily accessible reagents, O as a green oxidant, and gram-scale ability. Notably, the final S-S bond formation and cascade ring construction follow a radical pathway, which has been recognized via a radical trapping experiment with BHT during the course of the reaction. Notably, the exocyclic C═N bond at position 3 of 1,2-dithiole possesses stereochemistry.
已开发出一种操作简单且高效的多米诺礼节，可在无任何催化剂和添加剂存在的情况下，在室温下、在开放空气中，使用易于获得的二硫酯作为三原子 CCS 合成子，以及芳基异硫氰酸酯作为二原子 CS 单元，轻松构建 1,2-二硫杂环戊烷。该反应高效进行，以良好的收率得到具有各种不同电子和空间性质的各种官能团的所需的 1,2-二硫杂环戊烷。该方法避免了可能的毒性和繁琐的后处理条件，并且具有易于操作、廉价且易于获得的试剂、O 作为绿色氧化剂，以及克级规模的能力。值得注意的是，最终的 S-S 键形成和级联环构建遵循自由基途径，这已通过反应过程中用 BHT 进行的自由基捕获实验得到确认。值得注意的是，1,2-二硫杂环戊烷 3 位的环外 C═N 键具有立体化学。
