Asymmetric hydrogenation of ketones: tactics to achieve high reactivity, enantioselectivity, and wide scope.
Ru complexes with chiral diphosphines and amine-based ligands achieve high catalytic activity and enantioselectivity for the hydrogenation of ketones under neutral to slightly basic conditions. The chiral environment is controllable by changing the combination of these two ligands. A concerted six-membered transition state is proposed to be the origin of the high reactivity. The eta(6)-arene/TsDPEN-Ru and MsDPEN-Cp(*)Ir catalysts effect the asymmetric reaction under slightly acidic conditions. A variety of chiral secondary alcohols are obtained in high enantiomeric excess.
Division of Chemical Process Engineering, Graduate School of Engineering, Hokkaido University, Hokkaido, Japan. ohkuma@eng.hokudai.ac.jp
Takeshi
T
Ohkuma
D000588:Amines / Q000737:chemistry; D002384:Catalysis; D005029:Ethylenediamines; D006865:Hydrogenation; D007659:Ketones / Q000737:chemistry*; D009942:Organometallic Compounds; D013237:Stereoisomerism
D000588:Amines; D005029:Ethylenediamines; D007659:Ketones; D009942:Organometallic Compounds; C520782:ruthenium-(1S,2S)-N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine