| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348914 | Tetrahedron: Asymmetry | 2006 | 10 Pages |
The results of the reduction of chiral β-enamino ketones with sodium borohydride in acetic acid are reported. The reaction is convenient, stereoselective and high yielding and allows the preparation of enantiopure γ-amino alcohols in syn diastereoselectivity. The reaction is easy to perform and does not require expensive or hazardous chemicals. A mechanistic hypothesis is presented. The absolute configuration of the products obtained is attributed by correlating 1H NMR spectral data with conformational analysis performed by molecular modelling, and confirmed by X-ray analysis.
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(R,R)-1-Phenyl-3-{[(1R)-1-phenylethyl]amino}butan-1-olC18H23NOEe = 98%[α]D20=+3.3 (c 4.7, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (R,R,R)
(1S,2R)-2-((1R)-1-{[(1R)-1-Phenylethyl]amino}ethyl)cyclohexanolC16H25NOEe = 98%[α]D20=-36.4 (c 0.3, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (1S,2R,1′R,1″R)
(1R,2R)-2-((1R)-1-{[(1R)-1-Phenylethyl]amino}ethyl)-1,2,3,4-tetrahydronaphthalen-1-olC20H25NOEe = 98%[α]D20=-159.8 (c 0.8, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (R,R,R,R)
(2S,4R)-1,1,1-Trifluoro-4-{[(1R)-1-phenylethyl]amino}pentan-2-olC13H18F3NOEe = 98%[α]D20=-83.5 (c 0.6, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (2S,4R,1′R)
(2R,4R)-1,1,1-Trifluoro-4-{[(1R)-1-phenylethyl]amino}pentan-2-olC13H18F3NOEe = 98%[α]D20=-32.5 (c 0.1, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (R,R,R)
(1S,3S)-4,4,4-Trifluoro-1-phenyl-3-{[(1R)-1-phenylethyl]amino}butan-1-olC18H20F3NOEe = 98%[α]D20=+148.6 (c 0.8, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (2S,4S,1′R)
(1R,3R)-4,4,4-Trifluoro-1-phenyl-{[(1R)-1-phenylethyl]amino}butan-1-olC18H20F3NOEe = 98%[α]D20=-20.4 (c 0.6, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (R,R,R)
(1R,3R)-3-{[(1R)-1-(1-Naphthyl)ethyl]amino}-1-phenylbutan-1-olC22H25NOEe = 98%[α]D20=-2.5 (c 0.6, CHCl3)Source of chirality: (R)-1-naphthylethylamineAbsolute configuration: (R,R,R)
(1S,3S)-3-{[(1R)-1-(1-Naphthyl)ethyl]amino}-1-phenylbutan-1-olC22H25NOEe = 98%[α]D20=-3.4 (c 0.6, CHCl3)Source of chirality: (R)-1-naphthylethylamineAbsolute configuration: (1S,3S,1′R)
(4R,6R)-4,6-Dimethyl-3-[(1R)-1-phenylethyl]-1,3-oxazinan-2-oneC14H19NO2Ee = 98%[α]D20=+35.5 (c 3.4, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (R,R,R)
(4R,6S)-4-Methyl-6-phenyl-3-[(1R)-1-phenylethyl]-1,3-oxazinan-2-oneC19H21NO2Ee = 98%[α]D20=+18.3 (c 1.6, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (4R,6S,1′R)
(4R,4aS,10bS)-4-Methyl-3-[(1R)-1-phenylethyl]-3,4,4a,5,6,10b-hexahydro-2H-naphtho[2,1-e][1,3]oxazin-2-oneC21H23NO2Ee = 98%[α]D20=+126.7 (c 0.8, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (4R,4aS,10bS,1R)
(4R,6S)-4,6-Dimethyl-3-[(1R)-1-phenylethyl]-1,3-oxazinaneC14H21NOEe = 98%[α]D20=-48.1 (c 3.1, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (4R,6S,1′R)
(R,R)-4-Methyl-6-phenyl-3-[(1R)-1-phenylethyl]-1,3-oxazinaneC19H23NOEe = 98%[α]D20=-32.8 (c 2.0, CHCl3)Source of chirality: (R)-1-phenylethylamineAbsolute configuration: (R,R,R)
