59255-66-2Relevant academic research and scientific papers
Base-Mediated Generation of Ketenimines from Ynamides: [3+2] Annulation with Azaallyl Anions
D'Hollander, Agathe C. A.,Romero, Eugénie,Vijayakumar, Kamsana,Le Houérou, Camille,Retailleau, Pascal,Dodd, Robert H.,Iorga, Bogdan I.,Cariou, Kevin
supporting information, p. 2903 - 2908 (2021/04/21)
Under basic conditions and heat, ynamides can serve as precursors to ketenimines, whose synthetic potential is often hampered by their difficulty of access. Herein, we report that they can undergo a [3+2] cycloaddition with 2-azaallyl anions, obtained from benzylimines under the same reaction conditions. This reaction between two highly reactive intermediates, both generated in situ from bench stable starting materials, gives access to various nitrogen-rich heterocycles. The reaction usually proceeds with excellent diastereoselectivity, in favor of the cis adduct. Deuteration experiments and DFT calculations helped rationalize the regio- and stereoselectivity of the process as well as the formation of side products. (Figure presented.).
N-Protection of amines using pyridinium 2,2,2-trifluoroacetate ionic liquid as an efficient and reusable catalyst
Karimian, Somaye,Tajik, Hassan
, p. 218 - 220 (2014/02/14)
A simple, green, and efficient method for the N-tert-butoxycarbonylation of amines by pyridinium 2,2,2-trifluoroacetate ([Py][OTf]) as an efficient and reusable catalyst is reported. In general, electron donating groups on aryl group give rise to the higher yields than electron withdrawing groups. Clean reaction, short reaction times, high yields, reusability of catalyst, and easy preparation of it are some advantages of this work.
Axially chiral dicarboxylic acid catalyzed activation of quinone imine ketals: Enantioselective arylation of enecarbamates
Hashimoto, Takuya,Nakatsu, Hiroki,Takiguchi, Yuka,Maruoka, Keiji
supporting information, p. 16010 - 16013 (2013/11/19)
The synthetic utility of quinone imine ketals in the context of asymmetric catalysis was disclosed for the first time. By expanding the utility of chiral Bronsted acid catalysis to the electrophilic activation of quinone imine ketals, we succeeded in the development of highly enantioselective arylation of encarbamates to give α-amino-β-aryl ethers wherein quinone imine ketals act as functionalized aromatic ring surrogate. Further transformations of the products were also examined to establish procedures to provide chiral β-aryl amines and α-aryl esters.
Guanidine hydrochloride as an organocatalyst for N-Boc protection of amino groups
Jahani, Fatemeh,Tajbakhsh, Mahmood,Golchoubian, Hamid,Khaksar, Samad
supporting information; experimental part, p. 1260 - 1264 (2011/04/15)
A simple and efficient method for the chemoselective N-Boc protection of the amine moiety in a variety of compounds is described using di-tert-butyl dicarbonate and guanidine hydrochloride as an organocatalyst in ethanol at 35-40°C. Selective mono-N-Boc protection of diamines and chemoselective protection of hydroxylamines without formation of any side products is achieved. Amino acids and peptides are N-Boc protected efficiently in excellent yields under convenient reaction conditions.
Unprecedented direct conversion of N-N and N=N bonds to N-(tert-butyloxy)carbamates
Chandrasekhar,Raji Reddy,Jagadeeshwar Rao
, p. 1561 - 1562 (2007/10/03)
For the first time a one step direct conversion of aromatic hydrazines and azo compounds to N-(tert-butoxycarbonyl) amines is achieved via reductive cleavage of N-N and N=N bonds using the inexpensive and safe hydride source polymethylhydrosiloxane (PMHS) and di-tert-butyl dicarbonate [(Boc)2O] in the presence of a catalytic amount of 10% Pd-C.
1,4-Diaryl-2-oxo-1,2-dihydro-quinoline-3-carboxylic acids as endothelin receptor antagonists
Mederski, Werner W. K. R.,Osswald, Mathias,Dorsch, Dieter,Christadler, Maria,Schmitges, Claus-Jochen,Wilm, Claudia
, p. 1883 - 1886 (2007/10/03)
The discovery, synthesis and structure-activity relationships of a series of novel 1,4-diaryl-2-oxo-1 ,2-dihydro-quinoline-3-carboxylic acids as non-selective endothelin ET(A)/ET(B) receptor antagonists are described. The most potent inhibitor 3m displaye
Synthesis of Novel Imidazobenzodiazepines as Probes of the Pharmacophore for "Diazepam-Insensitive" GABAA Receptors
Zhang, Puwen,Zhang, Weijiang,Liu, Ruiyan,Harris, Bradford,Skolnick, Phil,Cook, James M.
, p. 1679 - 1688 (2007/10/02)
The syntheses of a series of novel imidazobenzodiazepines and their affinities for diazepam sensitive (DS) and diazepam insensitive (DI) GABAA receptors are described.Imidazobenzodiazepines belong to one of the very few chemical families which
