Copper-catalyzed [1,2]-rearrangements of allylic iodides and aryl α-diazoacetates
作者:Bin Xu、Jackson A. Gartman、Uttam K. Tambar
DOI:10.1016/j.tet.2017.01.048
日期:2017.7
iodonium ylides are synthetically useful reactions for the generation of functionalized α-iodoesters. Allylic iodides are coupled with α-diazoesters in the presence of a copper catalyst and a ligand to generate iodonium ylides, which undergo metal-mediated rearrangements. By fine-tuning the structure of the ligand, we have reversed the regioselectivity of copper-catalyzed reactions of iodonium ylides from
碘鎓碘化物的[1,2]-和[2,3]重排是合成有用的反应,用于生成功能化的α-碘代酯。烯丙基碘化物在铜催化剂和配体存在下与α-重氮酸酯偶合,生成碘鎓碘化物,这些碘化物经历金属介导的重排。通过微调配体的结构,我们通过使用替代联吡啶配体逆转了铜催化的碘鎓碘化物从[2,3]-到[1,2]重排的区域选择性。通过使用大体积的芳基α-重氮酯底物,进一步提高了对[1,2]-重排的偏爱。以高收率(高达88%的收率)和高区域选择性(高达> 95:5的区域异构体比率)生成了几种具有多种官能团范围的α-碘代酯。