Palladium-Catalyzed Intermolecular Oxidative Coupling Reactions of (<i>Z</i>)-Enamines with Isocyanides through Selective β-C(sp<sup>2</sup>)-H and/or C=C Bond Cleavage
two efficient palladium‐catalyzed intermolecular oxidative couplingreactions of (Z)‐enamines with isocyanides via selective β‐C(sp2)‐H and/or C=C bond cleavage have been developed, leading to controllable chemodivergent and stereoselective construction of a wide range of (E)‐β‐carbamoylenamine derivatives containing strong intramolecular hydrogen bonds. Furthermore, possible reaction pathways for these
Organocatalyzed regioselective and enantioselective synthesis of 1,4- and 1,2-dihydropyridines
作者:Truong-Giang Le、Hoai-Thu Pham、James P. Martin、Isabelle Chataigner、Jean-Luc Renaud
DOI:10.1080/00397911.2020.1778034
日期:2020.9.1
first examples of asymmetric organocatalyzed synthesis of 1,2-dihydropyridines, affording enantioselective access to and partially solving regioselectivity challenges in the synthesis of dihydropyridines. We demonstrate that through modification of organocatalysts both 1,2- and 1,4-dihydropyridines (1,2- and 1,4-DHPs) can be obtained with high regioselectivity (ratio of 1,2-DHP/1,4-DHP from 95/5 to 0/100)
Conjugate Addition of 3-Buytn-2-one to Anilines in Ethanol: Alkene Geometric Insights through In Situ FTIR Monitoring
作者:David R. Chisholm、Roy Valentine、Ehmke Pohl、Andrew Whiting
DOI:10.1021/acs.joc.6b01110
日期:2016.9.2
A convenient, mild and effective conjugateaddition of 3-butyn-2-one to a variety of anilines in ethanol is reported. The reaction was monitored and characterized through in situ FTIR, and the dynamics of the facile E/Z alkene geometry interconversion of the resultant aniline-derived enaminones was explored through NMR, FTIR and X-ray crystallography. A straightforward purification protocol that employs
Efficient Synthesis of Pyrazoles: Oxidative CC/NN Bond-Formation Cascade
作者:Julia J. Neumann、Mamta Suri、Frank Glorius
DOI:10.1002/anie.201002389
日期:2010.10.11
Golden section: A novel synthetic strategy for the synthesis of tetrasubstituted pyrazoles is provided. In an efficient CC/NNbond‐formation cascade, enamines and nitriles are oxidatively coupled to deliver pyrazoles in good yields (see scheme). The ready availability of the starting materials, the high level of practicability of the reaction and work up, and the avoidance of hydrazine starting materials
黄金部分:提供了一种合成四取代吡唑的新颖合成策略。在有效的C CC / NN键形成级联反应中,烯胺和腈氧化偶联以高产率提供吡唑(请参阅方案)。起始原料的容易获得,反应和后处理的高度实用性以及避免使用肼起始原料,使得该方法具有吸引力。
Transition-metal-free synthesis of β-trifluoromethylated enamines with trifluoromethanesulfinate
We have developed a transition-metal free trifluoromethylation protocol between enamines and CF3SO2Na. A wide range of β-trifluoromethyl substituted enamines were delivered in moderate to high yields with only E-configurations.