| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345476 | Tetrahedron: Asymmetry | 2015 | 17 Pages |
Functionalized α-oximinoketones with β-alkoxy, β-alkyl, and β-sulfenyl groups were used as efficient synthons for the preparation of chiral 1-acyl-4-imidazolin-2-ones and 1-acylimidazolidin-2-ones. For the preparation of the former heterocycles, α-oximinoketones were transformed into their respective imidazole N-oxides by neutral treatment with a chiral triazine, followed by reaction with acetic or propionic anhydrides to furnish the desired chiral 1-acetyl- or 1-propionyl-4-imidazolin-2-ones in moderate overall yields. Upon palladium hydroxide-catalyzed hydrogenation, these series were converted into their corresponding 1-acylimidazolidin-2-ones in high diastereoisomeric ratios. Thus, these novel chiral 1-acetyl- and 1-propionyl-imidazolidin-2-ones were obtained with a variety of alkyl groups at the C-4 and C-5 positions of the heterocycle, through a three-step methodology, and can be applied as new potential chiral auxiliaries.
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(S)-4-(Methoxymethyl)-5-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC14H18N2O2[α]D25 = +94.8 (c 0.29, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-(Ethoxymethyl)-5-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC15H20N2O2[α]D26 = +63.7 (c 0.186, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-(Isopropoxymethyl)-5-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC16H22N2O2[α]D26 = +58.6 (c 0.11, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-Methyl-1-(1-phenylethyl)-4-(phenylthiomethyl)-1H-imidazole 3-oxideC19H20N2OS[α]D27 = −39.1 (c 0.0197, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-((4-Chlorophenylthio)methyl)-5-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC19H19ClN2OS[α]D25 = −61.1 (c 0.157, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-((4-Bromophenylthio)methyl)-5-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC19H19BrN2OS[α]D28 = −57.4 (c 0.19, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4,5-Diethyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC15H20N2O[α]D24 = +99.8 (c 0.489, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-Ethyl-5-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC14H18N2O[α]D23 = +6.8 (c 1.614, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-Ethyl-4-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC14H18N2O[α]D26 = +101.7 (c 0.168, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-Methyl-1-(1-phenylethyl)-4-propyl-1H-imidazole 3-oxideC15H20N2O[α]D24 = +97.6 (c 0.101, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-(4-Methoxyphenyl)-4-methyl-1-(1-phenylethyl)-1H-imidazole 3-oxideC19H20N2O2[α]D27 = −37.3 (c 0.26, MeOH)Source of chirality: (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-5-((4-chlorophenylthio)methyl)-4-methyl-3-(1-phenylethyl)-1H-imidazol-2(3H)-oneC21H21ClN2O2S[α]D27 = +26.8 (c 0.306, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-5-((4-bromophenylthio)methyl)-4-methyl-3-(1-phenylethyl)-1H-imidazol-2(3H)-oneC21H21BrN2O2S[α]D25 = −65.7 (c 0.087, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-4,5-dimethyl-3-(1-phenylethyl)-1H-imidazol-2(3H)-oneC15H18N2O2[α]D25 = −52.25 (c 1.68, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-4,5-diethyl-3-(1-phenylethyl)-1H-imidazol-2(3H)-oneC17H22N2O2[α]D26 = +46.5 (c 0.142, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-5-ethyl-4-methyl-3-(1-phenylethyl)-1H-imidazol-2(3H)-oneC16H20N2O2[α]D22 = −50.0 (c 0.13, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-4-ethyl-5-methyl-3-(1-phenylethyl)-1H-imidazol-2(3H)-oneC16H20N2O2[α]D26 = −6.0 (c 0.133, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-4-methyl-3-(1-phenylethyl)-5-propyl-1H-imidazol-2(3H)-oneC17H22N2O2[α]D28 = +46.5 (c 0.142, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-1-Acetyl-4-(4-methoxyphenyl)-5-methyl-3-(-1-phenylethyl)-1H-imidazol-2(3H)-oneC21H22N2O3[α]D26 = −10.2 (c 0.188, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4,5-Dimethyl-3-(1-phenylethyl)-1-propionyl-1H-imidazol-2(3H)-oneC16H20N2O2[α]D29 = −55.2 (c 0.29, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4,5-Diethyl-3-(1-phenylethyl)-1-propionyl-1H-imidazol-2(3H)-oneC18H24N2O2[α]D26 = −8.25 (c 0.257, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-Ethyl-4-methyl-3-(1-phenylethyl)-1-propionyl-1H-imidazol-2(3H)-oneC17H22N2O2[α]D26 = −46.35 (c 0.255, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-Methyl-3-(1-phenylethyl)-1-propionyl-5-propyl-1H-imidazol-2(3H)-oneC18H24N2O2[α]D26 = −48.6 (c 0.195, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-4-(4-Methoxyphenyl)-5-methyl-3-(1-phenylethyl)-1-propionyl-1H-imidazol-2(3H)-oneC22H24N2O3[α]D26 = −10.4 (c 0.091, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-(Acetoxymethyl)-4-methyl-1-(1-phenylethyl)-1H-imidazoleC15H18N2O2[α]D22 = −44.1 (c 0.068, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-(Acetoxymethyl)-4-ethyl-1-(1-phenylethyl)-1H-imidazoleC16H20N2O2[α]D26 = −18.1 (c 0.086, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-(Acetoxymethyl)-1-(1-phenylethyl)-4-propyl-1H-imidazoleC17H22N2O2[α]D29 = −14.4 (c 0.202, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(4S,5R)-1-Acetyl-4,5-dimethyl-3-((S)-1-phenylethyl)imidazolidin-2-oneC15H20N2O2[α]D26 = +1.7 (c 0.241, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-1-Acetyl-4,5-diethyl-3-((S)-1-phenylethyl)imidazolidin-2-oneC17H24N2O2[α]D25 = −11.6 (c 0.093, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-1-Acetyl-4-ethyl-5-methyl-3-((S)-1-phenylethyl)imidazolidin-2-oneC16H22N2O2[α]D26 = −15.35 (c 0.057, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-1-Acetyl-4-methyl-3-((S)-1-phenylethyl)-5-propylimidazolidin-2-oneC17H24N2O2[α]D21 = −21.15 (c 0.101, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-1-Acetyl-4-(4-methoxyphenyl)-5-methyl-3-((S)-1-phenylethyl)imidazolidin-2-oneC21H24N2O3[α]D22 = −15.8 (c 0.061, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-4,5-Dimethyl-3-((S)-1-phenylethyl)-1-propionylimidazolidin-2-oneC16H22N2O2[α]D25 = +7.6 (c 0.651, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-4,5-Diethyl-3-((S)-1-phenylethyl)-1-propionylimidazolidin-2-oneC18H26N2O2[α]D26 = −16.1 (c 0.259, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(4S,5R)-4-(4-Methoxyphenyl)-5-methyl-3-((S)-1-phenylethyl)-1-propionylimidazolidin-2-oneC22H26N2O3[α]D26 = −23.3 (c 0.171, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (4S,5R)
(S)-4,5-Diethyl-1-(1-phenylethyl)-1H-imidazol-2(3H)-oneC15H20N2O[α]D25 = −11.4 (c 0.109, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-Ethyl-4-methyl-1-(1-phenylethyl)-1H-imidazol-2(3H)-oneC14H18N2O[α]D26 = +6.1 (c 0.053, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
(S)-5-(4-Methoxyphenyl)-4-methyl-1-(1-phenylethyl)-1H-imidazol-2(3H)-oneC19H20N2O2[α]D26 = −12.5 (c 0.401, MeOH)Source of chirality: organic synthesis starting from (S)-(−)-α-methylbenzylamineAbsolute configuration: (S)
