| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1344745 | Tetrahedron: Asymmetry | 2010 | 6 Pages |
Chiral cyclohexane-based phosphinothioureas were found to be efficient organocatalysts for the enantioselective intramolecular Morita–Baylis–Hillman reaction of ω-formyl-enone. Among the solvents screened, t-BuOH was the best one which provided good yield and enantioselectivity. Moreover in the presence of 3 mol % of phosphinothiourea 2b, the desired products were obtained in good-to-excellent yields with up to 98% ee under mild reaction conditions.
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(S)-(6-Hydroxycyclohex-1-enyl)(phenyl)methanoneC13H14O2Ee = 85%[α]D25=-36.1 (c 0.42, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(3-Bromophenyl)(6-hydroxycyclohex-1-enyl)methanoneC13H13BrO2Ee = 63%[α]D25=-8.7 (c 0.23, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(4-Bromophenyl)(6-hydroxycyclohex-1-enyl)methanoneC13H13BrO2Ee = 75%[α]D25=-20.0 (c 0.35, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(3-Chlorophenyl)(6-hydroxycyclohex-1-enyl)methanoneC13H13ClO2Ee = 65%[α]D25=-16.3 (c 0.40, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(4-Chlorophenyl)(6-hydroxycyclohex-1-enyl)methanoneC13H13ClO2Ee = 79%[α]D25=-21.3 (c 0.46, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(4-Fluorophenyl)(6-hydroxycyclohex-1-enyl)methanoneC13H13FO2Ee = 83%[α]D25=-31.8 (c 0.33, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(6-Hydroxycyclohex-1-enyl)(naphthalen-2-yl)methanoneC17H12O2Ee = 83%[α]D25=-36.8 (c 0.38, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(6-Hydroxycyclohex-1-enyl)(o-tolyl)methanoneC14H16O2Ee = 66%[α]D25=-7.6 (c 0.46, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(6-Hydroxycyclohex-1-enyl)(m-tolyl)methanoneC14H16O2Ee = 90%[α]D25=-32.0 (c 0.39, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(6-Hydroxycyclohex-1-enyl)(p-tolyl)methanoneC14H16O2Ee = 93%[α]D25=-48.6 (c 0.36, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(6-Hydroxycyclohex-1-enyl)(4-methoxyphenyl)methanoneC14H16O3Ee = 97%[α]D25=-51.0 (c 0.31, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(4-(Dimethylamino)phenyl)(6-hydroxycyclohex-1-enyl)methanoneC15H19NO2Ee = 98%[α]D25=-55.2 (c 0.30, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
(S)-(6-Hydroxycyclohex-1-enyl)(thiophen-2-yl)methanoneC11H12O2SEe = 76%[α]D25=-40.4 (c 0.26, CHCl3)Source of chirality: asymmetric MBH reactionAbsolute configuration: (S)
