Disulfonimide‐Catalyzed Asymmetric Reduction of
<i>N</i>
‐Alkyl Imines
作者:Vijay N. Wakchaure、Philip S. J. Kaib、Markus Leutzsch、Benjamin List
DOI:10.1002/anie.201504052
日期:2015.9.28
A chiral disulfonimide (DSI)‐catalyzedasymmetric reduction of N‐alkyl imines with Hantzsch esters as a hydrogen source in the presence of Boc2O has been developed. The reaction delivers Boc‐protectedN‐alkyl amines with excellent yields and enantioselectivity. The method tolerates a large variety of alkyl amines, thus illustrating potential for a general reductive cross‐coupling of ketones with diverse
A novel cationic [IrH(THF)(P,N)(imine)] [BArF] catalyst containing a P-stereogenic MaxPHOX ligand is described for the direct asymmetrichydrogenation of N-methyl and N-alkyl imines. This is the first catalytic system to attain high enantioselectivity (up to 94% ee) in this type of transformation. The labile tetrahydrofuran ligand allows for effective activation and reactivity, even at low temperatures