Intermolecular cyclization of N-methylanilines and maleimides to tetrahydroquinolines via K2S2O8 promoted C(sp3)–H activation
作者:Arvind K. Yadav、Lal Dhar S. Yadav
DOI:10.1016/j.tetlet.2016.02.078
日期:2016.3
A metal-free, novel and convenient way for the direct cyclization of N-methylanilines with maleimides to tetrahydroquinolines via C(sp3)–H activation is reported. The protocol utilizes inexpensive and easy to handle K2S2O8 as a radical surrogate and involves sequential formation of C(sp3)–C(sp2) and C(sp2)–C(sp2) bonds in a one-pot procedure at room temperature. The method affords excellent yield of
报道了一种无金属的,新颖且方便的方法,用于通过C(sp 3)–H活化将N-甲基苯胺与马来酰亚胺直接环化为四氢喹啉。该协议利用廉价且易于处理的K 2 S 2 O 8作为自由基替代物,涉及一个序列中依次形成C(sp 3)–C(sp 2)和C(sp 2)–C(sp 2)键。室温下锅法。该方法提供了具有生物学上重要的四氢喹啉核心的三环化合物的优异产率。
Visible light photoredox catalysis with N-hydroxyphthalimide for [4+2] cyclization between N-methylanilines and maleimides
作者:Arvind K. Yadav、Lal Dhar S. Yadav
DOI:10.1016/j.tetlet.2016.12.077
日期:2017.2
An efficient [4+2] cyclization of N-methylanilines with maleimides to afford tetrahydroquinolines using N-hydroxyphthalimide as a metal-free and cheap organophotoredox catalyst is reported. The protocol involves C(sp(3))-H activation of N-methylanilines for the formation of alpha-amino radical without an oxidant at room temperature. The present method describes an easy preparation of tricyclic heterocycles in good to excellent yields under mild reaction conditions. 2016 Elsevier Ltd. All rights reserved.