A new iron-catalyzed, direct C-H amination of azoles at C2 has been developed by usingformamides or amines as nitrogen sources. Imidazole is the only additive in the catalyst system and oxygen in air is employed during the transformation process.
Catalyst- and Reagent-Free Electrochemical Azole C−H Amination
作者:Youai Qiu、Julia Struwe、Tjark H. Meyer、João C. A. Oliveira、Lutz Ackermann
DOI:10.1002/chem.201802832
日期:2018.9.3
Catalyst‐ and chemical oxidant‐free electrochemical azole C−H aminations were accomplished via cross‐dehydrogenative C−H/N−H functionalization. The catalyst‐free electrochemical C−H amination proved feasible on azoles with high levels of efficacy and selectivity, avoiding the use of stoichiometric oxidants under ambient conditions. Likewise, the C(sp3)−H nitrogenation proved viable under otherwise
Going to the source: Formamides or parentamines were used as an aminogroupsource for the silver‐mediated amination of benzoxazoles. Although reactions with formamides proceeded at high temperatures, the directamination with amines took place under much milder conditions (see scheme). Optically active aminogroups could also be installed without racemization.
Cooperative Catalysis with Aldehydes and Copper: Development and Application in Aerobic Oxidative CH Amination at Room Temperature
作者:Yinjun Xie、Bo Qian、Pan Xie、Hanmin Huang
DOI:10.1002/adsc.201200944
日期:2013.5.3
formation of an aminal, hydrolysis of the aminal to generate the copper‐amide species, subsequent CH amination and re‐oxidation of copper(I) to copper(II) by oxygen. It not only provides an efficient method to realize the oxidative CH amination of benzoxazoles with free amines at room temperature, but also paves the way for establishing new CN bond formation reactions by using this efficient cooperative
Cobalt- and Manganese-Catalyzed Direct Amination of Azoles under Mild Reaction Conditions and the Mechanistic Details
作者:Ji Young Kim、Seung Hwan Cho、Jomy Joseph、Sukbok Chang
DOI:10.1002/anie.201005922
日期:2010.12.17
azoles has been developed using peroxide and an acid additive to couple various types of azoles with ammonia, and primary or secondary amines (see scheme). The catalyst loadings are low, the optimal reaction conditions are mild, and the substrate scope is broad. The product azoles are an important pharmacophore of high biological activity.