乙二醛,甲基乙二醛,苯基乙二醛,丁烷-2,3-二酮,苯甲酰和环己烷-1,2-二酮的双-(对-硝基苯基)hydr和一些双-(对-溴苯基)structures的结构通过ir,1 H nmr和13 C nmr光谱。通常,from的E,E形式是从直接合成中获得的,除了环己烷-1,2-二酮的双-(对-硝基苯基)hydr和苯基乙二醛和苯乙二醛的双-(对-溴苯基)hydr酮外,它们是Ë,ž-螯合物形式。从HMPA中分离出乙二醛,2,3-丁烷和丁二酮的双-(对硝基苯基)hydr的不稳定黄色结晶形式,其中含有两个结晶的六甲基磷酰胺(HMPA)分子,其中可能包含E,Z-异构体。解决方案。一系列的E,E -osa的四乙酸铅氧化使脱氢成为1,2-双偶氮乙烯。E,Z -osa的相似氧化主要产生2-芳基-1,2,3-三唑类产物(osotriazoles),同时偶氮乙烯的产率较低。环己烷-1,2-二酮双-(对硝基苯基)
A versatile copper-catalyzed [3 + 1 + 1] annulation of oximes and isocyanates with AgNO3 is described. In this conversion, AgNO3 and isocyanates instead of conventional azide or diazonium reagents were used as the nitrogen source. This three-component transformation was achieved by cleaving N–O/C–H/C–N bonds and building C═N/N–N bonds, which provides a strategy to prepare N-2-aryl-1,2,3-triazoles with
Catalyst-Free Regioselective N<sup>2</sup> Arylation of 1,2,3-Triazoles Using Diaryl Iodonium Salts
作者:Sahar Roshandel、Maiko J. Lunn、Golam Rasul、Daniel Sylvinson Muthiah Ravinson、Suresh C. Suri、G. K. Surya Prakash
DOI:10.1021/acs.orglett.9b02140
日期:2019.8.16
The widespread application of 1,2,3-triazoles in pharmaceuticals has resulted in substantial interest toward developing efficient postmodification methods. Whereas there are many postmodification methods available to obtain N-1-substituted 1,2,3-triazoles, developing a selective and convenient protocol to synthesize N-2-aryl-1,2,3-triazoles has been challenging. We report a catalyst-free and regioselective method to access N-2-aryl-1,2,3-triazoles in good to excellent yields (66-97%). This scalable postmodification protocol is effective for a wide range of substrates.