Access to Wieland-Miescher ketone in an enantiomerically pure form by a kinetic resolution with yeast-mediated reduction.
Both enantiomers of Wieland-Miescher ketone [3,4,8, 8a-tetrahydro-8a-methyl-1,6(2H,7H)-naphthalenedione], in a highly enantiomerically enriched form, became readily available by a newly developed kinetic resolution with yeast-mediated reduction. From a screening of yeast strains, Torulaspora delbrueckii IFO 10921 was selected. The collected cells of this strain, obtained by an incubation in a glucose medium, smoothly reduced only the isolated carbonyl group of the (S)-enantiomer, while the (R)-enantiomer remained intact. Starting from both enantiomers ( approximately 70% ee) prepared by an established proline-mediated asymmetric Robinson annulation, the reduction with T. delbrueckii gave the (R)-enantiomer (98% ee) and the corresponding alcohol (4aS,5S)-4,4a, 5,6,7,8-hexahydro-5-hydroxy-4a-methyl-2(3H)-naphthalenone (94% ee, 94% de) in preparative scale in nearly quantitative yields. An approach for the asymmetric synthesis of the Wieland-Miescher ketone was also successful. 2-Methyl-2-(3-oxobutyl)-1,3-cyclohexanedione, the prochiral precursor, was reduced with this strain to give a cyclic acetal form of (2S, 3S)-3-hydroxy-2-methyl-2-(3-oxobutyl)cyclohexanone, in a stereomerically pure form.
Fuhshuku
K
K
Department of Chemistry, Keio University, 3-14-1, Hiyoshi, Yokohama 223-8522, Japan.
Funa
N
N
Akeboshi
T
T
Ohta
H
H
Hosomi
H
H
Ohba
S
S
Sugai
T
T
D007659:Ketones / Q000737:chemistry*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D004718:Saccharomycetales / Q000378:metabolism*; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism
D007659:Ketones