| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1350554 | Tetrahedron: Asymmetry | 2007 | 6 Pages |
A novel organocatalytic asymmetric cyclopropanation of α,β-unsaturated aldehydes with arsonium ylides using diphenylprolinol silylether as a catalyst is described. A variety of chiral cyclopropyl aldehydes are obtained in moderate to good yields with up to 99:1 dr (diastereomeric ratio) and 99% ee under simple and mild reaction conditions.
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(1R,2S,3R)-2-Benzoyl-3-phenyl-cyclopropanecarbaldehydeC17H14O2Ee = 98%[α]D25=-167.7 (c 0.50, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Fluorobenzoyl)-3-phenyl-cyclopropanecarbaldehydeC17H13FO2Ee = 97%[α]D25=-137.1 (c 0.34, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Chlorobenzoyl)-3-phenyl-cyclopropanecarbaldehydeC17H13ClO2Ee = 96%[α]D26=-86.4 (c 0.48, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Bromobenzoyl)-3-phenyl-cyclopropanecarbaldehydeC17H13BrO2Ee = 96%[α]D26=-80.6 (c 1.00, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Nitrobenzoyl)-3-phenyl-cyclopropanecarbaldehydeC17H13NO4Ee = 98%[α]D26=-119.1 (c 0.43, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Methylbenzoyl)-3-phenyl-cyclopropanecarbaldehydeC18H16O2Ee = 98%[α]D26=-81.4 (c 0.34, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Methoxybenzoyl)-3-phenyl-cyclopropanecarbaldehydeC18H16O3Ee = 98%[α]D25=-174.6 (c 0.27, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-Benzoyl-3-methyl-cyclopropanecarbaldehydeC12H12O2Ee = 78%[α]D25=-6.1 (c 0.76, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-Benzoyl-3-propyl-cyclopropanecarbaldehydeC14H16O4Ee = 96%[α]D25=-16.4 (c 1.38, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
(1R,2S,3R)-2-(4-Bromobenzoyl)-3-propyl-cyclopropanecarbaldehydeC14H15BrO2Ee = 95%[α]D26=-38.6 (c 0.27, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,3R)
