通过无催化剂的2-氨基吡啶溴化物与芳烃亚磺酸钠的一锅反应,可以合成3-(芳硫基)咪唑并[1,2 - a ]吡啶-2(3H)-醇。串联反应涉及分子内酰胺化,然后进行亚磺酰化,并以中等至极好(33-85%)的产率提供了多种3-(芳硫基)咪唑并[1,2 - a ]吡啶-2(3H)-醇。该方法具有广泛的底物范围,具有宽泛的官能团耐受性,适用于克级合成。
An efficient access to 2,3-diarylimidazo[1,2-a]pyridines via imidazo[1,2-a]pyridin-2-yl triflate through a Suzuki cross-coupling reaction-direct arylation sequence
An efficient method to prepare 2,3-diarylimidazo[1,2-a]pyridines is described. The procedure involves a Suzuki cross-coupling reaction followed by a directarylation at position 3. Imidazo[1,2-a]pyridin-2-yl triflate was identified as a suitable coupling partner, permitting access to a variety of highly functionalized 2,3-diarylimidazo[1,2-a]pyridines.
描述了一种制备2,3-二芳基咪唑并[1,2- a ]吡啶的有效方法。该过程涉及Suzuki交叉偶联反应,然后在3位直接芳基化。咪唑并[1,2- a ]吡啶-2-基三氟甲磺酸酯被确定为合适的偶联伴侣,从而可以使用各种高度官能化的2, 3-二芳基咪唑并[1,2- a ]吡啶。
Metal-free synthesis of pyridin-2-yl ureas from 2-aminopyridinium salts
作者:Saroj、Om P.S. Patel、Krishnan Rangan、Anil Kumar
DOI:10.1016/j.tetlet.2019.07.030
日期:2019.8
domino approach has been developed for the synthesis of pyridin-2-yl urea derivatives via the reaction of 2-aminopyridinium salts and arylamines. The developed strategy tolerated a wide range of functional groups and afforded pyridin-2-yl ureas in moderate to good yields. The reaction was postulated to involve tandem cyclization, intermolecular nucleophilic addition, ring opening, and demethylation.
Relationship between structure and photoinitiating abilities of selected bromide salts of 2-oxo-2,3-dihydro-1<i>H</i>-imidazo[1,2-<i>a</i>]pyridine (IMP): influence of the solvent and the substitution in benzaldehyde on the course of its reaction with IMP
2-a]pyridinium bromide and its C3-substituted derivatives have been synthesized and structurally characterized by X-ray crystallography and quantum chemical calculations. Their potential as photoinitiators for free-radical polymerization has been investigated experimentally and compared with theoretical results. It has been established that the course of the reaction that introduces the substituted benzylidene group