Simm Peter E, Sekar Prakash, Richardson Jeffery, Davies Paul W
School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.
Lilly U.K., Erl Wood Manor, Windlesham GU20 6PH, U.K.
ACS Catal. 2021 Jun 4;11(11):6357-6362. doi: 10.1021/acscatal.1c01457. Epub 2021 May 13.
The combination of nucleophilic nitrenoids and π-acid catalysis has emerged as a powerful tool in heterocycle synthesis. Accessing more varied heterocycle-substitution patterns by maintaining the same reaction pathways across different alkynes remains a challenge. Here we show that Au(I) catalysis of isoxazole-based nitrenoids with alkynyl thioethers provides controlled access to (3 + 2) annulation by a regioselective addition β to the sulfenyl group. The reaction with isoxazole-containing nitrenoids delivers sulfenylated pyrroles and indoles as single regioisomers bearing useful functional groups and structural variety.
亲核氮宾与π-酸催化的结合已成为杂环合成中的一种强大工具。通过在不同炔烃中保持相同的反应途径来获得更多样化的杂环取代模式仍然是一个挑战。在此，我们表明，金（I）催化异恶唑基氮宾与炔硫醚反应，通过对亚磺酰基进行区域选择性β-加成，可实现对（3 + 2）环化反应的可控合成。与含异恶唑的氮宾反应可生成亚磺酰化的吡咯和吲哚，它们是具有有用官能团和结构多样性的单一区域异构体。
