| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1349642 | Tetrahedron: Asymmetry | 2006 | 7 Pages |
The asymmetric transfer hydrogenation promoted by the (R,R)-(Ts-DPEN)–Ru complex of some 1-ferrocenyl-1,3-diketones was investigated and in all the cases only the carbonyl group distant to the metallocene moiety was reduced with variable selectivity depending on the C-3 substituent. The CBS-catalyzed reduction of 1-ferrocenyl-β-hydroxy-1-ketones, previously protected as acetates, was also found effective, giving both the corresponding syn- and anti-1,3-diols in satisfactory enantiomeric purity.
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(R)-1-Ferrocenyl-3-phenyl-3-hydroxypropane-1 oneC19H18FeO2Ee = >99% (by chiral HPLC)[α]D = +18.2 (c 0.88, CHCl3)Source of chirality: asymmetric reduction of 1-ferrocenyl-3-phenylpropane-1,3-dioneAbsolute configuration: R
(1S,3R)-1-Ferrocenyl-3-phenyl-1,3-dihydroxypropaneC19H20FeO2Ee = >99% (by chiral HPLC)[α]D = +29.3 (c 0.15, CHCl3)Source of chirality: (R)-1-ferrocenyl-3-phenyl-3-hydroxypropane-1-oneAbsolute configuration: 1S,3R
(1R,3R)-1-Ferrocenyl-3-phenyl-1,3-dihydroxypropaneC19H20FeO2Ee = >99% (by chiral HPLC)[α]D = +15.2 (c 0.21, CHCl3)Source of chirality: (R)-1-ferrocenyl-3-phenyl-3-hydroxypropane-1-oneAbsolute configuration: 1R,3R
(1S,3R)-1-Ferrocenyl-1,3-dihydroxy-4-methylpentaneC16H22FeO2Ee = 94% (by chiral HPLC)[α]D = +35.3 (c 0.36, CHCl3)Source of chirality: asymmetric reduction of (±)-1-ferrocenyl-3-hydroxy-4-methylpentane-1-oneAbsolute configuration: 1S,3R
(1S,3S)-1-Ferrocenyl-1,3-dihydroxy-4-methylpentaneC16H22FeO2Ee = 87% (by chiral HPLC)[α]D = +7.8 (c 0.65, CHCl3)Source of chirality: asymmetric reduction of (±)-1-ferrocenyl-3-hydroxy-4-methylpentane-1-oneAbsolute configuration: 1S,3S
