13437-79-1Relevant articles and documents
Chiral Bronsted Acids Catalyze Asymmetric Additions to Substrates that Are Already Protonated: Highly Enantioselective Disulfonimide-Catalyzed Hantzsch Ester Reductions of NH-Imine Hydrochloride Salts
Wakchaure, Vijay N.,Obradors, Carla,List, Benjamin
supporting information, p. 1707 - 1712 (2020/08/28)
While imines are frequently used substrates in asymmetric Bronsted acid catalysis, their corresponding salts are generally considered unsuitable reaction partners. Such processes are challenging because they require the successful competition of a catalytic amount of a chiral anion with a stoichiometric amount of an achiral one. We now show that enantiopure disulfonimides enable the asymmetric reduction of N-H imine hydrochloride salts using Hantzsch esters as hydrogen source. Our scalable reaction delivers crystalline primary amine salts in great efficiency and enantioselectivity and the discovery suggests potential of this approach in other Bronsted acid catalyzed transformations of achiral iminium salts. Kinetic studies and acidity data suggest a bifunctional catalytic activation mode.
Synthesis of α-Substituted Primary Benzylamines through Copper-Catalyzed Cross-Dehydrogenative Coupling
Kramer, S?ren
supporting information, p. 65 - 69 (2019/01/04)
A copper-catalyzed route to α-substituted, primary benzylamines by C-H functionalization of alkylarenes is described. The method directly affords the amine hydrochloride salt. Catalyst loadings down to 0.1 mol % in combination with scalability, insensitivity to air and moisture, and no need for column chromatography makes the procedure highly practical. The facile synthesis of the racemate of a blockbuster drug highlights the relevance for the development of pharmaceuticals. Preliminary mechanistic data are also included.
Diethylenetriamine-Mediated Direct Cleavage of Unactivated Carbamates and Ureas
Noshita, Megumi,Shimizu, Yuhei,Morimoto, Hiroyuki,Ohshima, Takashi
supporting information, p. 6062 - 6065 (2016/12/09)
Diethylenetriamine is effective for the direct cleavage of unactivated carbamates and ureas without additional reagents and catalysts. Various carbamates and ureas were cleaved to afford products in good yield, and the reactions were not affected by air or moisture. Unique chemoselective cleavage of carbamate and urea in the presence of amides was also achieved.
