| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347040 | Tetrahedron: Asymmetry | 2014 | 6 Pages |
Two chiral aromatic l-prolinamides were synthesized in high overall yield (95%) from N-Boc-l-proline and served as organocatalysts in asymmetric Michael reactions of aldehydes to nitroalkenes. Under the optimized reaction conditions, (S)-N-tritylpyrrolidine-2-carboxamide 4 was found to be a highly efficient organocatalyst for the Michael addition, and the corresponding Michael adducts were obtained in good yields (up to 94%), with excellent enantioselectivities (up to 99% ee) and diastereoselectivities (up to 99:1 dr).
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tert-Butyl (S)-2-(benzhydrylcarbamoyl)pyrrolidine-1-carboxylateC24H34N2O4[α]D20 = −78.6 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (S)
(S)-N-Benzhydrylpyrrolidine-2-carboxamideC18H20N2O[α]D20 = −59.1 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (S)
tert-Butyl (S)-2-(tritylcarbamoyl)pyrrolidine-1-carboxylateC29H32N2O3[α]D20 = −38.4 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (S)
(S)-N-Tritylpyrrolidine-2-carboxamideC24H24N2O[α]D20 = −27.0 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (S)
(2R,3S)-2-Methyl-4-nitro-3-phenylbutanalC11H13NO3[α]D20 = +8.3 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Ethyl-4-nitro-3-phenylbutanalC12H15NO3[α]D20 = +8.8 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(R)-2-((S)-2-Nitro-1-phenylethyl)pentanalC13H17NO3[α]D20 = +6.8 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Isopropyl-4-nitro-3-phenylbutanalC13H17NO3[α]D20 = +25.5 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-3-(4-Bromophenyl)-2-ethyl-4-nitrobutanalC12H14BrNO3[α]D20 = +7.6 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-3-(4-Bromophenyl)-2-ethyl-4-nitrobutanalC12H14ClNO3[α]D20 = +9.5 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-3-(2-Chlorophenyl)-2-ethyl-4-nitrobutanalC12H14ClNO3[α]D20 = +11.8 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Ethyl-3-(4-methoxyphenyl)-4-nitrobutanalC13H17NO4[α]D20 = +10.4 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Ethyl-4-nitro-3-(p-tolyl)butanalC13H17NO3[α]D20 = +13.1 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Ethyl-4-nitro-3-(4-(trifluoromethyl)phenyl)butanalC13H14F3NO3[α]D20 = +9.8 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3R)-2-Ethyl-3-(furan-2-yl)-4-nitrobutanalC10H13NO4[α]D20 = +17.2 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Isopropyl-4-nitro-3-(p-tolyl)butanalC14H19NO3[α]D20 = +66.1 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-3-(4-Bromophenyl)-2-isopropyl-4-nitrobutanalC13H16BrNO3[α]D20 = +92.5 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-2-Isopropyl-4-nitro-3-(p-tolyl)butanalC14H19NO3[α]D20 = +78.3 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
(2R,3S)-3-(2-Chlorophenyl)-2-isopropyl-4-nitrobutanalC13H16ClNO3[α]D20 = +107.1 (c 1.0, CHCl3)Source of chirality: newAbsolute configuration: (2R,3S)
(2R,3R)-2-Isopropyl-4-nitro-3-(thiophen-2-yl)butanalC11H15NO3S[α]D20 = +29.3 (c 1.0, CHCl3)Source of chirality: the precursorAbsolute configuration: (2R,3S)
