| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347544 | Tetrahedron: Asymmetry | 2008 | 6 Pages |
A novel bifunctional thiourea–tertiary-amine-catalyzed enantioselective Friedel–Craft-type addition reaction of 2-naphthol with β,γ-unsaturated α-keto ester was developed. Subsequent dehydration of the reaction adducts with a catalytic amount of concentrated H2SO4 in a one-pot fashion readily afforded a series of new optically active naphthopyran derivatives with moderate to good yields (up to 91%) and enantioselectivities (up to 90%).
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(S)-Methyl 1-phenyl-1H-benzo[f]chromene-3-carboxylateC21H16O3Ee = 87%[α]D22=-341.6 (c 0.50, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Ethyl 1-phenyl-1H-benzo[f]chromene-3-carboxylateC22H18O3Ee = 82%[α]D20=-290.5 (c 0.50, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Isopropyl 1-phenyl-1H-benzo[f]chromene-3-carboxylateC23H20O3Ee = 84%[α]D21=-182.9 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Allyl 1-phenyl-1H-benzo[f]chromene-3-carboxylateC25H18O3Ee = 84%[α]D22=-112.2 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Benzyl 1-phenyl-1H-benzo[f]chromene-3-carboxylateC27H20O3Ee = 78%[α]D22=-147.4 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 1-(4-bromophenyl)-1H-benzo[f]chromene-3-carboxylateC21H20BrO3Ee = 87%[α]D22=-350.9 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 1-(4-chlorophenyl)-1H-benzo[f]chromene-3-carboxylateC21H20ClO3Ee = 87%[α]D22=-369.7 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 1-(4-fluorophenyl)-1H-benzo[f]chromene-3-carboxylateC21H20FO3Ee = 86%[α]D22=-290.6 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 1-(4-ethoxyphenyl)-1H-benzo[f]chromene-3-carboxylateC23H20O4Ee = 72%[α]D22=-278.6 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 1-(4-nitrophenyl)-1H-benzo[f]chromene-3-carboxylateC21H20NO5Ee = 90%[α]D22=-417.2 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 1-(3-chlorophenyl)-1H-benzo[f]chromene-3-carboxylateC21H20ClO3Ee = 86%[α]D22=-341.0 (c 0.34, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(R)-Methy 1-(2-bromophenyl)-1H-benzo[f]chromene-3-carboxylateC21H20BrO3Ee = 57%[α]D23=-102.3 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (R)
(S)-Methyl 1-(2,5-dimethoxyphenyl)-1H-benzo[f]chromene-3-carboxylateC23H20O5Ee = 60%[α]D21=-241.4 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 8-bromo-1-phenyl-1H-benzo[f]chromene-3-carboxylateC21H20BrO3Ee = 86%[α]D23=-273.1 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-Methyl 9-methoxy-1-phenyl-1H-benzo[f]chromene-3-carboxylateC22H18O4Ee = 82%[α]D23=-325.5 (c 0.50, CHCl3);Source of chirality: asymmetric synthesisAbsolute configuration: (S)
