| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345332 | Tetrahedron: Asymmetry | 2015 | 7 Pages |
A simple and efficient stereoselective synthesis of synargentolide B was achieved by using ethyl (S)-2-hydroxypropanoate as a readily available starting material. The key steps involved in the synthesis are Horner–Wadsworth–Emmons olefination, Sharpless asymmetric dihydroxylation, zinc allylation, and Hoveyda–Grubbs IInd generation catalyzed ring closing metathesis.
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(S)-Ethyl 2-(tert-butyldimethylsilyloxy)propanoateC11H24O3Si[α]D25 = −25.1 (c 2.5, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoateAbsolute configuration: (S)
(4R,5S)-Ethyl 5-(tert-butyldimethylsilyloxy)-4-hydroxyhex-2-ynoateC14H26O4Si[α]D25 = +3.4 (c 2.5, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reactionAbsolute configuration: (4R,5S)
(4R,5S)-Ethyl 4,5-bis(tert-butyldimethylsilyloxy)hex-2-ynoateC20H40O4Si2[α]D25 = −9.1 (c 2.3, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reactionAbsolute configuration: (4R,5S)
(6R,7S,E)-Ethyl 6,7-bis(tert-butyldimethylsilyloxy)oct-2-en-4-ynoateC22H42O4Si2[α]D25 = −11.7 (c 3.0, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reactionAbsolute configuration : (6R,7S,E)
(6R,7S,E)-6,7-Bis(tert-butyldimethylsilyloxy)oct-2-en-4-yn-1-olC20H40O3Si2[α]D25 = −14.2 (c 3.2, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reactionAbsolute configuration: (6R,7S,E)
(5R,6S)-5-((E)-5-(4-Methoxybenzyloxy)pent-3-en-1-ynyl)-2,2,3,3,6,8,8,9,9-nonamethyl-4,7-dioxa-3,8-disiladecaneC28H48O4Si2[α]D25 = −10.5 (c 3.4, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reactionAbsolute configuration: (5R,6S,E)
(2R,3R,6R,7S)-6,7-Bis(tert-butyldimethylsilyloxy)-1-(4-methoxybenzyloxy)oct-4-yne-2,3-diolC28H50O6Si2[α]D25 = −19.4 (c 3.4, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylationAbsolute configuration: (2R,3R,6R,7S)
(5R,6S)-5-((E)-5-(((4R,5R)-5-((4-Methoxybenzyloxy)methyl)-2,2-dimethyl1,3dioxolan-4-yl)ethynyl)-2,2,3,3,6,8,8,9,9-nonamethyl-4,7-dioxa-3,8-disiladecaneC31H54O6Si2[α]D25 = +18.2 (c 1.4, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylationAbsolute configuration: (5R,6S,E,R,R)
(2S,3R)-5-((4R,5R)-5-((4-Methoxybenzyloxy)methyl)-2,2-dimethyl-1,3-dioxolan-4-yl)pent-4-yne-2,3-diolC19H26O6[α]D25 = +32.9 (c 1.7, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylationAbsolute configuration: (2S,3R,R,R)
(2S,3R,E)-5-((4R,5R)-5-((4-Methoxybenzyloxy)methyl)-2,2-dimethyl-1,3-dioxolan-4-yl)pent-4-ene-2,3-diolC19H28O6[α]D25 = +9.5 (c 1.1, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylationAbsolute configuration: (2S,3R,E,R,R)
(2S,3R,E)-5-((4R,5R)-5-((4-Methoxybenzyloxy)methyl)-2,2-dimethyl-1,3-dioxolan-4-yl)pent-4-ene-2,3-diyl diacetateC23H32O8[α]D25 = +3.2 (c 1.3, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylationAbsolute configuration: (2S,3R,E,R,R)
(2S,3R,E)-5-((4R,5R)-5-(Hydroxymethyl)-2,2-dimethyl-1,3-dioxolan-4-yl)pent-4-ene-2,3-diyl diacetateC15H24O7[α]D25 = +13.2 (c 0.26, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylationAbsolute configuration: (2S,3R,E,R,R)
(2S,3R,E)-5-((4R,5R)-5-((R)-1-(Acryloyloxy)but-3-enyl)-2,2-dimethyl-1,3-dioxolan-4-yl)pent-4-ene-2,3-diyl diacetateC22H32O7[α]D25 = +18.3 (c 0.8, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylation, zinc allylationAbsolute configuration: (2S,3R,E,R,R,R)
(2S,3R,E)-5-((4R,5R)-2,2-Dimethyl-5-((R)-6-oxo-3,6-dyhydro-2H-pyran-2-yl)-1,3-dioxolan-4-yl)pent-4-ene-2,3-diyl diacetateC19H26O8[α]D25 = +42.2 (c 0.2, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylation, zinc allylationAbsolute configuration: (2S,3R,E,R,R,R)
(2S,3R,6R,7S,E)-6,7-Dihydroxy-7-((R)-6-oxo-3,6-dyhydro-2H-pyran-2-yl)hept-4-ene-2,3-diyl diacetateC16H22O8[α]D25 = +24.8 (c 0.4, CHCl3)Source of chirality: (S)-ethyl 2-hydroxypropanoate, LiHMDS reaction, Sharpless asymmetric dihydroxylation, zinc allylationAbsolute configuration: (2S,3R,6R,7S,E,R)
