An efficient reduction of N -substituted carbonylimidazolides into formamides by NaBH 4
作者:Zhiyong Chen、Yiming Cao、Zeyu Tian、Xuan Zhou、Wenjin Xu、Jia Yang、Hanbing Teng
DOI:10.1016/j.tetlet.2017.04.072
日期:2017.5
A novel, simple and versatile protocol was investigated for highly efficient synthesis of formamides through reducing N-substituted carbonylimidazolides by NaBH4 under mild reaction conditions. By this method, not only carboxylic acids or isocyanates, but also amines can readily access formamides with high yields.
Synthesis of unsymmetrical biaryl ureas from N-carbamoylimidazoles: kinetics and application
作者:Tristan Rawling、Andrew M. McDonagh、Bruce Tattam、Michael Murray
DOI:10.1016/j.tet.2012.05.002
日期:2012.7
N-Carbamoylimidazoles dissociate in solution to yield imidazole and an isocyanate that may be reacted with another arylamine to form an unsymmetrical biaryl urea. This paper investigates the reaction kinetics and the influence of electron withdrawing/donating substituents on the reaction of N-carbamoylimidazoles with aniline. The overall reactionmechanism involves two zwitterionic intermediates,
Efficient Solid-Phase Synthesis of Disubstituted 1,3-Dihydro-imidazol-2-ones
作者:Gérard Rossé、Julie Strickler、Marcel Patek
DOI:10.1055/s-2004-831316
日期:——
A bromoacetal linker was used to achieve the synthesis of ureas on a solid support. The resulting ureido acetals were treated with TFA and were converted in an intramolecular cyclization via N-acyliminium ion to disubstituted 1,3-dihydro-imidazol-2-ones.
Diastereoselective intramolecular cyclization/Povarov reaction cascade for the one-pot synthesis of polycyclic quinolines
作者:E. A. Kuznetsova、A. V. Smolobochkin、T. S. Rizbayeva、A. S. Gazizov、J. K. Voronina、O. A. Lodochnikova、D. P. Gerasimova、A. B. Dobrynin、V. V. Syakaev、D. N. Shurpik、I. I. Stoikov、A. R. Burilov、M. A. Pudovik、O. G. Sinyashin
DOI:10.1039/d2ob01031c
日期:——
method for the synthesis of complex alkaloid-like aza-heterocycles has been developed through the Povarov reaction of in situ generated 2-oxoimidazolium cations. The reaction lead to the formation of 2 C–N, 2 C–C bonds and three stereocentres, and features excellent regio- and diastereoselectivity. Based on the controlled experiments and quantum chemistry data, the mechanism of the reaction cyclization
A versatile way for the synthesis of monomethylamines by reduction of <i>N</i>-substituted carbonylimidazoles with the NaBH<sub>4</sub>/I<sub>2</sub> system
作者:Lin Chen、Xuan Zhou、Zhiyong Chen、Changxu Wang、Shunjie Wang、Hanbing Teng
DOI:10.3762/bjoc.18.104
日期:——
yields from a wide range of raw materials including amines (primaryamines and secondaryamines), carboxylic acids and isocyanates. Besides, an interesting reduction selectivity was observed. Exploration of the reaction process shows that it undergoes a two-step pathway via a formamide intermediate and the reduction of the formamide intermediate to monomethylamine as the rate-determining step. This