Scope of enantioselective palladium(II)-catalyzed aerobic alcohol oxidations with (-)-sparteine.
Evaluation of the substrate scope for Pd(II)/ (-)-sparteine catalyzed aerobic oxidative kinetic resolution of secondary alcohols is disclosed. An improved system is found with use of tert-butyl alcohol solvent in which benzylic and aliphatic alcohols as well as alcohols containing olefins are effectively oxidatively resolved. For substrates that successfully undergo oxidative kinetic resolution, k(rel) values are generally between 10 and 20. Successful scale-up of various substrates to 10-mmol scale is described. Extension to oxidative desymmetrization of 1,3-meso-diols is successful with enantiomeric excesses ranging from 78 to 85%.
Mandal
Sunil K
SK
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City 84112, USA.
Jensen
David R
DR
Pugsley
Jacob S
JS
Sigman
Matthew S
MS
D000438:Alcohols / Q000032:analysis / Q000737:chemistry*; D002384:Catalysis; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D013034:Sparteine / Q000737:chemistry*; D013237:Stereoisomerism
D000438:Alcohols; D013034:Sparteine; D010165:Palladium