| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348104 | Tetrahedron: Asymmetry | 2012 | 7 Pages |
A simple and efficient stereoselective synthesis of clonostachydiol was achieved using ethyl (R)-3-hydroxybutanoate 5 and methyl (R)-2-hydroxypropanoate 12 as readily available starting materials. The key steps involved in the synthesis were MacMillan α-hydroxylation, Horner–Wadsworth–Emmons (HWE) olefination, a Grignard reaction, and Hoveyda–Grubbs IInd generation catalyzed ring closing metathesis (RCM).
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Ethyl (R)-3-(tert-butyldimethylsilyloxy)butanoateC12H26O3Si[α]D25=-30.5 (c 2, CHCl3)Source of Chirality: Ethyl (R)-3-hydroxybutanoateAbsolute configuration: (3R)
Methyl (R,E)-5-(tert-butyldimethylsilyloxy)hex-2-enoateC13H26O3Si[α]D25=-9.8 (c 1.8, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoateAbsolute configuration: (5R,E)
Methyl (R)-5-(tert-butyldimethylsilyloxy)hexanoateC13H28O3Si[α]D25=-13.3 (c 2.9, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoateAbsolute configuration: (5R)
Ethyl (4R,7R,E)-7-(tert-butyldimethylsilyloxy)-4-hydroxyoct-2-enoateC16H32O4Si[α]D25=-13.1 (c 0.8, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation-olefinationAbsolute configuration: (4R,7R,E)
Ethyl (4R,7R,E)-7-(tert-butyldimethylsilyloxy)-4-(4-methoxybenzyloxy)oct-2-enoateC24H40O5Si[α]D25=+13.8 (c 1.1, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation–olefinationAbsolute configuration: (4R,7R,E)
(4R,7R,E)-7-(tert-butyldimethylsilyloxy)-4-(4-methoxybenzyloxy)oct-2-enoic acidC22H36O5Si[α]D25=-29.6 (c 0.8, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation-olefinationAbsolute configuration: (4R,7R,E)
Methyl (R)-2-(tert-butyldimethylsilyloxy)propanoateC10H22O3Si[α]D25=+25.3 (c 2.8, CHCl3)Source of chirality: Methyl (R)-2-hydroxypropanoateAbsolute configuration: (2R)
(2R,3S)-3-(Benzyloxy)pent-4-en-2-yloxy(tert-butyl)C18H30O2Si[α]D25=+10.3 (c 3, CHCl3)Source of chirality: Methyl (R)-2-hydroxypropanoate, Grignard reactionAbsolute configuration: (2R,3S)
(2R,3S)-3-(Benzyloxy)pent-4-en-2-olC12H16O2[α]D25=+18.9 (c 3.3, CHCl3)Source of chirality: Methyl (R)-2-hydroxypropanoate, Grignard reactionAbsolute configuration: (2R,3S)
(4R,7R,E)-((2R,3S)-3-(Benzyloxy)pent-4en-2-yl)7-(tert-butyldimethylsilyloxy)-4-(4-methoxybenzyloxy)oct-2-enoateC34H50O6Si[α]D25=-14.3 (c 0.17, CHCl3)Source of Chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation–olefination, methyl (R)-2-hydoxypropanoate, Grignard reactionAbsolute configuration: (2R,3S,4R,7R,E)
(4R,7R,E)-((2R,3S)-3-(Benzyloxy)pent-4-en-2-yl)7-hydroxy-4-(4-methoxybenzyloxy)oct-2-enoateC28H36O6[α]D25=+6.2 (c 0.4, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation-olefination, methyl (R)-2-hydoxypropanoate, Grignard reactionAbsolute configuration: (2R,3S,4R,7R,E)
(4R,7R,E)-((2R,3S)-3-(Benzyloxy)pent-4en-2-yl)7-acryloyloxy)-4-(4-methoxybenzyloxy)oct-2-enoateC31H38O7[α]D25=+2.5 (c 0.2, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation–olefination, methyl (R)-2-hydoxypropanoate, Grignard reactionAbsolute configuration: (2R,3S,4R,7R,E)
(4R,7R,E)-((2R,3S)-3-Hydroxypent-4-en-2-yl)7-(acryloyloxy)-4-hydroxyoct-2-enoateC16H24O6[α]D25=-10.7 (c 0.65, CHCl3)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation–olefination, methyl (R)-2-hydoxypropanoate, Grignard reactionAbsolute configuration: (2R,3S,4R,7R,E)
ClonostachydiolC28H36O6[α]D25=+101.6 (c 0.5, MeOH)Source of chirality: Ethyl (R)-3-hydroxybutanoate, l-proline catalyzed α-aminoxylation-olefination, methyl (R)-2-hydoxypropanoate, Grignard reactionAbsolute configuration: (2R,3S,8R,11R,4E,12E)
