5857-45-4Relevant academic research and scientific papers
Metal- and base-free synthesis of imidazo[1,2-: A] pyridines through elemental sulfur-initiated oxidative annulation of 2-aminopyridines and aldehydes
Tan, Jing,Ni, Penghui,Huang, Huawen,Deng, Guo-Jun
supporting information, p. 4227 - 4230 (2018/06/21)
The elemental sulfur-promoted oxidative cyclization reaction for the efficient synthesis of substituted imidazo[1,2-a]pyridines has been developed. Easily available 2-aminopyridines and aldehydes were directly assembled in a highly atom-economical fashion through oxidative annulation under metal- and base-free conditions. Besides arylacetaldehydes, aliphatic aldehydes were also compatible with this system to deliver the alkyl-substituted imidazo[1,2-a]pyridines in excellent yields with the capability of gram-scale synthesis.
Silver-catalyzed cyclization of N-(prop-2-yn-1-yl)pyridin-2-amines
Chioua, Mourad,Soriano, Elena,Infantes, Lourdes,Jimeno, M. Luisa,Marco-Contelles, Jose,Samadi, Abdelouahid
supporting information, p. 35 - 39 (2013/02/22)
We report herein the silver-catalyzed cycloisomerization of readily available N-(prop-2-yn-1-yl)pyridine-2-amines as a new and practical method for the synthesis of differently substituted 3-methylimidazo[1,2-a]pyridines. The isomerization reactions proce
Synthesis of imidazo[1,2-a]pyridines: "Water-mediated" hydroamination and silver-catalyzed aminooxygenation
Chandra Mohan, Darapaneni,Nageswara Rao, Sadu,Adimurthy, Subbarayappa
supporting information, p. 1266 - 1272 (2013/08/24)
Aqueous syntheses of methylimidazo[1,2-a]pyridines without any deliberate addition of catalyst are reported. Imidazo[1,2-a]pyrazine and imidazo[2,1-a]isoquinoline were also obtained in good yields under similar conditions. With acetonitrile as solvent, Ag
Water mediated deprotective intramolecular hydroamination of N-propargylaminopyridines: Synthesis of imidazo[1,2-a]pyridines
Chandra Mohan, Darapaneni,Sarang, Niraj B.,Adimurthy, Subbarayappa
supporting information, p. 6077 - 6080 (2013/10/22)
Metal-free synthesis of substituted imidazole [1,2-a]pyridines from deprotective N-(prop-2-yn-1-yl)pyridin-2-amines in water is elucidated. Electron releasing substituents on pyridine ring provided pure products in quantitative yields without separation b
A base promoted cyclization of N-propargylaminopyridines. Synthesis of imidazo[1,2-a]pyridine derivatives
Husinec, Suren,Markovic, Rade,Petkovic, Milos,Nasufovic, Veselin,Savic, Vladimir
supporting information; experimental part, p. 2286 - 2289 (2011/06/21)
Chemical equations presented. A base promoted cyclization of the protected N-propargylaminopyridines was shown to be an efficient method for the preparation of imidazo[1,2-a]pyridine derivatives. The reactions were carried out with a small excess of base,
Acetylenchemie. 9. Mitt. Anellierte Imidazole aus N-Propinylamid-Vorstufen
Reisch, Johannes,Scheer, Mathias
, p. 677 - 679 (2007/10/02)
The compound 2-(N-formyl-N-prop-2'-inyl)aminopyridine was cyclised in boiling formic acid to 3-methylimidazopyridine, with 3-methylene-2H-imidazopyridine as the intermediate.Under similar conditions the 1,3-diprop-2-inylpyrimidoquinoline-2,4-dione resulted from 1-methylimidazoquinoline-4-carbonic acid-N-2-prop-2'-inylamide and from the 1-prop-2'inylbenzonaphthyridin-2-one the 1-methylbenzoimidazonaphthyridine-4,7-dione as a new ring system, was obtained.
The Rearrangements of 2-Nitroenamines in Acidic Solutions
Krowczynski, Adam,Kozerski, Lech
, p. 341 - 349 (2007/10/02)
2-Nitroenamines react in a concentrated sulfuric acid, methanolic sulfuric acid or in TFA solutions giving a variety of products such as: the amides of pyrogronic acid oxime, di- and tri- azaindenes, 1-N-oxide of methoxysubstituted quinoxaline, oxazole, pyrazole derivatives and 1,3-dinitro-4-alkylaminobutadienes-1,3.Each of the products can be selectively synthesized by changing reaction medium and a substituent on the enamine nitrogen.The mechanism of formation of these derivatives is discussed, in a few instances, on the basis of spectroscopic evidence found that the nitronic acid is the reactive species in acidic solution.
