已经描述了N 1-H-1,2,3-三唑的直接开环/亲核取代反应。发散的 ( Z )-β-卤素或磺酰基取代的烯酰胺可以以可调的方式立体定向合成。这种策略不仅可以在非金属催化和温和的反应条件下实现N 1-H-1,2,3-三唑的新开环方法,而且还为可靠地获得多功能 ( Z )-β-取代的烯酰胺提供了良好的机会可用作进一步合成转化的合成前体。
CO<sub>2</sub>/Photoredox-Cocatalyzed Tandem Oxidative Cyclization of α-Bromo Ketones and Amines To Construct Substituted Oxazoles
作者:Xiaowei Zhang、Yonghui He、Jing Li、Rui Wang、Lijun Gu、Ganpeng Li
DOI:10.1021/acs.joc.9b00283
日期:2019.6.21
CO2/photoredox-cocatalyzed tandem oxidative cyclization of α-bromo ketones and amines for the preparation of substituted oxazoles has been achieved. The avoidance of using both transition-metal catalysts and peroxides makes this method more sustainable and renewable.
Synthesis of Substituted Oxazoles by Visible-Light Photocatalysis
作者:Tanmay Chatterjee、Ji Young Cho、Eun Jin Cho
DOI:10.1021/acs.joc.6b00989
日期:2016.8.19
A simple and practical method for the synthesis of substituted oxazoles has been developed using readily available α-bromoketones and benzylamines by visible-light photocatalysis at room temperature. The process, which requires 1 mol % of [Ru(bpy)3]Cl2 photocatalyst with K3PO4 and CCl3Br, is effective for accessing a variety of valuable oxazole compounds. The synthetic utility of our protocol was also
已经开发了一种简单而实用的合成取代的恶唑的方法,该方法使用易得的α-溴代酮和苄胺,在室温下通过可见光光催化进行合成。该方法需要1摩尔%的具有K 3 PO 4和CCl 3 Br的[Ru(bpy)3 ] Cl 2光催化剂,可有效地获得各种有价值的恶唑化合物。我们的协议的合成效用也通过制备天然产物texaline得到了证明。
Copper(ii)-mediated oxidative cyclization of enamides to oxazoles
作者:Alison E. Wendlandt、Shannon S. Stahl
DOI:10.1039/c2ob25310k
日期:——
The copper(II)-mediated oxidative cyclization of enamides to oxazoles is reported. A range of 2,5-disubstituted oxazoles were prepared in moderate to good yields in two steps from simple amide and alkyne precursors.
An efficient synthesis of 2,5-disubstitutedoxazolesvia Co(III) catalysis is described herein. The synthesis is achieved under mild conditions through [3+2] cycloaddition of N-pivaloyloxyamides and alkynes. The reaction operates through an internal oxidation pathway and features a very broad substrate scope. The one-step synthesis of natural products such as texamine and balsoxin has been demonstrated
Formation of Acyl-Substituted Nitrile Ylides by Rh<sub>2</sub>(OAc)<sub>4</sub>-Catalyzed Decomposition of<i>α</i>-Diazocarbonyl Compounds in Nitriles
作者:Kazuaki Fukushima、Toshikazu Ibata
DOI:10.1246/bcsj.68.3469
日期:1995.12
The Rh2(OAc)4-catalyzed reactions of α-diazocarbonyl compounds in nitrile in the presence of dimethyl acetylenedicarboxylate (DMAD) gave oxazole and pyrrole derivatives. The formation of the oxazole derivatives is explained in terms of the 1,5-cyclization of an acyl-substituted nitrileylide intermediate, and the formation of the pyrrole derivatives is explained by the 1,3-dipolar cycloaddition of