protocol for direct C–H alkylation and acylation of N-heterocycles, using readily accessible carboxylic acids as radical precursors under visible-light irradiation without a photocatalyst and an additional acid additive, has been developed. This protocol provides expedient access to substituted N-heterocycles under mild and metal-free conditions. Mechanistic experiments indicate that this reaction proceeds
Synthesis of Isoquinolines and Heterocycle-Fused Pyridines via Three-Component Cascade Reaction of Aryl Ketones, Hydroxylamine, and Alkynes
作者:Liyao Zheng、Jia Ju、Yunhui Bin、Ruimao Hua
DOI:10.1021/jo3010414
日期:2012.7.6
An efficient one-pot synthesis of isoquinolines and heterocycle-fused pyridines by three-component reaction of aryl ketones, hydroxylamine, and alkynes is developed. The reaction involves condensation of aryl ketones and hydroxylamine, rhodium(III)-catalyzed C–H bond activation of the in situ generated aryl ketone oximes, and cyclization with internal alkynes. This protocol enables rapid assembly of
通过芳基酮,羟胺和炔烃的三组分反应,有效地一锅法合成异喹啉和杂环稠合吡啶。该反应涉及芳基酮和羟胺的缩合,铑(III)催化原位生成的芳基酮肟的C–H键活化以及与内部炔烃的环化作用。该协议能够从容易获得的底物中快速组装多取代的异喹啉以及γ-咔啉,呋喃[2,3- c ]吡啶,噻吩并[2,3- c ]吡啶和苯并呋喃[2,3- c ]吡啶。
Cobalt-catalyzed redox-neutral synthesis of isoquinolines: C–H activation assisted by an oxidizing N–S bond
作者:Fen Wang、Qiang Wang、Ming Bao、Xingwei Li
DOI:10.1016/s1872-2067(16)62491-9
日期:2016.8
A redox-neutral avenue to access isoquinolines has been realized by a Co(Ⅲ)-catalyzed C-H activation process. Starting from readily available N -sulfinyl imine substrates and alkynes, the reaction occurred via N-S cleavage with broad substrate scope and functional group compatibility in the presence of cost-effective cobalt catalysts.