1810-62-4Relevant academic research and scientific papers
The: P -toluenesulfonic acid catalyzed single pot synthesis of tetracyclic 1,2-dihydroquinolines: A metal free approach
Hajare, Anil K.,Jagdale, Arun R.,Shenoy, G. Gautham,Sinha, Neelima
supporting information, p. 4888 - 4890 (2016/07/06)
A simple, convenient and efficient p-toluenesulfonic acid catalyzed tandem reaction of aliphatic ketones with substituted anilines towards the synthesis of polysubstituted 1,2-dihydroquinolines has been developed. The ready availability of the catalyst, operational simplicity, cost effectiveness of the process and excellent regioselectivity mark some of the highlights of this methodology.
Highly active metal-free catalysts for hydrogenation of unsaturated nitrogen-containing compounds
Sumerin, Victor,Chernichenko, Konstantin,Nieger, Martin,Leskelae, Markku,Rieger, Bernhard,Repo, Timo
experimental part, p. 2093 - 2110 (2011/11/06)
New highly active ansa-ammonium borate catalysts for the direct metal-free hydrogenation of imines were prepared by tuning of the basicity and steric bulkiness of their amine moieties. The highest catalytic activity among previously reported organocatalytic systems was shown for a wide range of nitrogen-containing substrates. The first example of asymmetric imine hydrogenation based on the ansa-ammonium borate concept was demonstrated. Furthermore, effective catalyst recovery by extraction of the acidic solution with an organic solvent followed by dehydration with TMSBr was elaborated. The initial findings highlight the development of more effective chiral ansa-ammonium borates for enantioselective hydrogenation. Therefore, the progress achieved in the ansa-ammonium borate concept makes it very promising for further elaboration with the aim to obtain industrially applicable catalysts. Copyright
Scope and mechanistic study of the ruthenium-catalyzed ortho-C-H bond activation and cyclization reactions of arylamines with terminal alkynes
Yi, Chae S.,Yun, Sang Young
, p. 17000 - 17006 (2007/10/03)
The cationic ruthenium hydride complex [(PCy3) 2(CO)(CH3CN)2RuH]+BF 4- was found to be a highly effective catalyst for the C-H bond activation reaction of arylamines and terminal alkynes. The regioselective catalytic synthesis of substituted quinoline and quinoxaline derivatives was achieved from the ortho-C-H bond activation reaction of arylamines and terminal alkynes by using the catalyst Ru3-(CO)12/HBF 4·OEt2. The normal isotope effect (k CH/kCD = 2.5) was observed for the reaction of C 6H5NH2 and C6D5NH 2 with propyne. A highly negative Hammett value (ρ = -4.4) was obtained from the correlation of the relative rates from a series of meta-substituted anilines, m-XC6H4NH2, with σp in the presence of Ru3(CO)12/ HBF4·OEt2 (3 mol % Ru, 1:3 molar ratio). The deuterium labeling studies from the reactions of both indoline and acyclic arylamines with DC≡CPh showed that the alkyne C-H bond activation step is reversible. The crossover experiment from the reaction of 1-(2-amino-1-phenyl)pyrrole with DC≡CPh and HC≡CC6H4-p-OMe led to preferential deuterium incorporation to the phenyl-substituted quinoline product. A mechanism involving rate-determining ortho-C-H bond activation and intramolecular C-N bond formation steps via an unsaturated cationic ruthenium acetylide complex has been proposed.
Efficient microwave-assisted synthesis of quinolines and dihydroquinolines under solvent-free conditions
Ranu, Brindaban C.,Hajra, Alakananda,Dey, Suvendu S.,Jana, Umasish
, p. 813 - 819 (2007/10/03)
A convenient and efficient procedure for the synthesis of quinolines and dihydroquinolines has been developed by a simple one-pot reaction of anilines with alkyl vinyl ketones on the surface of silica gel impregnated with indium(III) chloride under microwave irradiation without any solvent.
