6304-27-4Relevant articles and documents
Reversible C-N Bond Formation in the Zirconium-Catalyzed Intermolecular Hydroamination of 2-Vinylpyridine
Griffin, Samuel E.,Pacheco, Javier,Schafer, Laurel L.
supporting information, p. 1011 - 1016 (2019/03/08)
The intermolecular hydroamination of alkenes with alkylamines has been a long-standing challenge in catalysis, partially due to the near-thermoneutral nature of this transformation. Consistent with this understanding, we report the direct observation of reversible C-N bond formation in hydroamination. A bis(ureate) zirconium complex catalyzed the intermolecular hydroamination of 2-vinylpyridine. Reversible C-N bond formation was characterized by variable-temperature NMR spectroscopy, and thermodynamic parameters were determined using van't Hoff plots. Isolated intermediates support an aza-Michael-addition mechanism. Sensitivity to steric bulk in the C-N bond forming step provided further evidence for the kinetically accessible but limited thermodynamic driving force for this transformation.
Aza-Michael-type addition reaction catalysed by a supported ionic liquid phase incorporating an anionic heteropoly acid
Ghasemi, Mohammad Hadi,Kowsari, Elaheh,Shafiee, Abbas
supporting information, p. 1150 - 1153 (2016/03/09)
In this work, we have obtained substituted amines under mild conditions in good yields using the Aza-Michael-type addition of various amines to vinyl compounds catalysed by a supported ionic liquid incorporating an anionic heteropoly acid. Different catalysts, including Lewis acids, Br?nsted acids and heteropoly acids were investigated in which heteropoly acids having dual Br?nsted and Lewis acid characteristics were excellent catalysts. The ionic liquid incorporating a polytungstate anion supported on magnetic diatomaceous earth as a magnetically separable heterogeneous catalyst offered the best results in terms of yield. The solid nanocatalyst was easily removed with a magnet.
Photocatalyzed [2 + 2 + 2]-cycloaddition of nitriles with acetylene: An effective method for the synthesis of 2-pyridines under mild conditions
Heller, Barbara,Sundermann, Bernd,Buschmann, Helmut,Drexler, Hans-Joachim,You, Jingsong,Holzgrabe, Ulrike,Heller, Eberhard,Oehme, Guenther
, p. 4414 - 4422 (2007/10/03)
The photocatalyzed [2 + 2 + 2]-cycloaddition of nitriles with 2 equiv of acetylene to 2-pyridines can be carried out under mild conditions and represents a valuable extension to common synthetical methods. For the ideal wavelength range (350-500 nm), lamps as well as sunlight can be used. Working at room temperature and in organic solvents such as toluene or hexane as well as in water gives satisfying results in many cases. However, it is also possible to vary the solvent and the reaction temperature of the photocatalyzed synthesis and to choose, with respect to the specific substrate, specific requirements for this particular reaction and general requirements of the method. This simple and selective method derives its potential mainly from the large variety of applicable nitriles. Suitable substrates include (functionalized) aliphatic and aromatic nitriles as well as cyanamides derived from secondary amines.