| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348960 | Tetrahedron: Asymmetry | 2007 | 14 Pages |
The Ni(acac)2 catalytic ZnEt2-mediated asymmetric Reformatsky-type reaction of Evans chiral imide with various acetophenones was studied. The chiral imido zinc enolate, which was formed through the metal–halogen exchange reaction of chiral α-bromopropionyl-2-oxazolidinones 2 with diethyl zinc under the catalysis of Ni(acac)2, performed the asymmetric zinc-Reformatsky reaction with activated α-haloacetophenones 3 to give the chiral β-hydroxyamide 4 in good yields and high ratios of syn-(2R,3R)-isomers (up to >97%). This new asymmetric synthesis technology affords a practical method to synthesize the versatile chiral building block 5 for triazole antifungal agents, such as Voriconazole, Ravuconazole, TAK-187, and RO-0094815.
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(S)-4-(1-Methylethyl)-5,5-diphenyl-2-oxazolidinoneC18H19NO2Ee >99%[α]D25=-255.2 (c 0.2, CHCl3)Source of chirality: l-valineAbsolute configuration: (S)
[3(2R,3R),4S]-4-Benzyl-3-[4-chloro-3-(2,4-difluorophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC21H20ClF2NO4De >98%[α]D25=+9.9 (c 1.0, CH2Cl2)Source of chirality: l-phenylalanineAbsolute configuration: (R,R,S)
[3(2R,3S),4S]-4-Benzyl-3-[4-chloro-3-(2,4-difluorophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC21H20ClF2NO4De >98%[α]D25=+32.8 (c 1.0, CH2Cl2)Source of chirality: l-phenylalanineAbsolute configuration: (S,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-(3-phenyl-3-hydroxy-2-methyl-1-oxobutyl)-2-oxazolidinoneC29H31NO4De >98%[α]D25=-127.3 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
[3(2R,3R),4S]-4-Benzyl-3-[4-chloro-3-(2,5-difluorophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC21H20ClF2NO4De >98%[α]D25=+7.7 (c 1.0, CH2Cl2)Source of chirality: l-phenylalanineAbsolute configuration: (R,R,S)
[3(2R,3S),4S]-4-Benzyl-3-[4-chloro-3-(2,5-difluorophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC21H20ClF2NO4De >98%[α]D25=+41.4 (c 1.0, CH2Cl2)Source of chirality: l-phenylalanineAbsolute configuration: (S,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-[4-chloro-3-(2,4-difluorophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC29H28ClF2NO4De >98%[α]D25=-110.7 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-[4-chloro-3-(2,5-difluorophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC29H28ClF2NO4De >98%[α]D25=-109.1 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-(4-chloro-3-phenyl-3-hydroxy-2-methyl-1-oxobutyl)-2-oxazolidinoneC29H30CINO4De >98%[α]D25=-112.5 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-[3-(4-methoxyphenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC30H33NO5De >98%[α]D25=-124.2 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-[3-(4-nitrophenyl)-3-hydroxy-2-methyl-1-oxobutyl]-2-oxazolidinoneC29H30N2O6De >98%[α]D25=-101.4 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
[3(2R,3R),4S]-5,5-Diphenyl-4-isopropyl-3-[4-chloro-3-(2,4-difluorophenyl)-3-hydroxy-2-ethyl-1-oxobutyl]-2-oxazolidinoneC30H30ClF2NO4De >98%[α]D25=-148.6 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R,S)
(2R,3R)-3-[3-(2,4-Difluorophenyl)-3,4-epoxy-2-methyl]butanoic acidC11H10F2O3De >97%[α]D25=-42.7 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R)
(2R,3R)-3-[3-(2,5-Difluorophenyl)-3,4-epoxy-2-methyl]butanoic acidC11H10F2O3De >97%[α]D25=-41.5 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R)
(2R,3R)-3-[3-(2,4-Difluorophenyl)-3-hydroxy-2-methyl-3-(1H-1,2,4-triazol-1-yl)]butanoic acidC13H13F2N3O3De >97%[α]D25=-52.4 (c 1.0, CH3OH)Source of chirality: l-valineAbsolute configuration: (R,R)
(2R,3R)-3-[3-(2,5-Difluorophenyl)-3-hydroxy-2-methyl-3-(1H-1,2,4-triazol-1-yl)]butanoic acidC13H13F2N3O3De >97%[α]D25=-43.1 (c 1.0, CH2Cl2)Source of chirality: l-valineAbsolute configuration: (R,R)
