کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1345371 | 980194 | 2007 | 14 صفحه PDF | دانلود رایگان |

Treatment of optically active 1-chlorovinyl p-tolyl sulfoxides, which were synthesized from symmetrical ketones or methyl formate and (R)-(−)-chloromethyl p-tolyl sulfoxide in three steps, with lithium enolate of carboxylic acid tert-butyl esters gave optically active adducts having a substituent (alkyl, alkoxy, or dibenzylamino group) at the α-position with high 1,4-chiral induction from the sulfur chiral center. The adducts were converted to optically active esters, lactic acid, and α-amino acid derivatives having a chiral center at the α-position. When this addition reaction was carried out with an ester enolate generated from excess carboxylic acid tert-butyl ester with LDA in the presence of HMPA, the diastereomer of the adduct was obtained. By using the two reaction conditions for the generation of the ester enolate, a new method for asymmetric synthesis of both enantiomers of carboxylic acid derivatives having a substituent at the α-position from the one chiral source, (R)-(−)-chloromethyl p-tolyl sulfoxide, was achieved.
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(R)-1-Chloro-2-methyl-1-(p-tolylsulfinyl)-1-propeneC11H13ClOSEe = 99%[α]D24=+156.2 (c 1.0, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-[Chloro-(p-tolylsulfiny)methylidene]cyclohexaneC14H17ClOSEe = 99%[α]D25=+213.0 (c 1.0, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-[Chloro-(p-tolylsulfinyl)methylidene]cyclopentadecaneC22H35ClOSEe = 99%[α]D24=+120.7 (c 1.3, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-1-Chloroethenyl p-tolyl sulfoxideC9H9ClOSEe = 99%[α]D25=+151.4 (c 0.8, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2,3,3-trimethyl-4-(p-tolylsulfonyl)butanoateC18H28O4SEe = 96%[α]D30=-14.3 (c 1.2, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclohexy}propionateC21H32O4SEe = 97%[α]D26=-5.3 (c 1.8, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclopentadecyl}propionateC30H50O4SEe = 97%[α]D24=-4.3 (c 0.9, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-ethyl-3,3-dimethyl-4-(p-tolylsulfonyl)butanoateC19H30O4SEe = 93%[α]D26=-3.0 (c 1.7, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclohexyl}butanoateC22H34O4SEe = 99%[α]D26=-4.9 (c 1.8, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclopentadecyl}butanoateC31H52O4SEe = 97%[α]D26=-1.7 (c 0.9, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-[1,1-dimethyl-2-(p-tolylsulfonyl)ethyl]hexanoateC21H34O4SEe = 96%[α]D28=-0.5 (c 2.8, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2R)-(−)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclopentadecyl}hexanoateC33H56O4SEe = 97%[α]D27=-1.9 (c 0.9, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(−)-2,3,3-Trimethylbutyric acidC7H14O2Ee = 96%[α]D28=-20.8 (c 0.7, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(+)-3-Benzyloxy-4,4-dimethyldihydrofuran-2-oneC13H16O3Ee = 99%[α]D28=+112.5 (c 0.22, CHCl3)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(+)-4-Benzyloxy-2-oxaspiro[4.5]decan-3-oneC16H20O3Ee = 97%[α]D27=+101.2 (c 0.91, CHCl3)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(+)-3-Dibenzylaminodihydrofuran-2-oneC18H19NO2Ee = 87%[α]D28=+26.5 (c 0.22, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(+)-3-Dibenzylamino-4,4-dimethyldihydrofuran-2-oneC20H23NO2Ee = 99%[α]D29=+137 (c 0.47, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(+)-4-Dibenzylamino-2-oxaspiro[4.5]decan-3-oneC23H27NO2Ee = 99%[α]D27=+91.5 (c 1.0, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(R)-(−)-(4,4-Dimethyl-2-oxotetrahydrofuran-3-yl)carbamic acid methyl esterC8H13NO4Ee = 99%[α]D28=-8.2 (c 1.0, CHCl3)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (R)
(2S)-(+)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclopentadecyl}propionateC30H50O4SEe = 99%[α]D23=+5.05 (c 1.34, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (S)
(2S)-(+)-tert-Butyl 2-{1-[(p-tolylsulfonyl)methyl]cyclopentadecyl}butanoateC31H52O4SEe = 99%[α]D25=+1.75 (c 0.45, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (S)
(2S)-(+)-tert-Butyl 2,3,3-trimethyl-4-(p-tolysulfonyl)butanoateC18H28O4SEe = 80%[α]D28=+9.8 (c 0.84, ethanol)Source of chirality: (R)-(−)-chloromethyl p-tolyl sulfoxideAbsolute configuration: (S)
Journal: Tetrahedron: Asymmetry - Volume 18, Issue 16, 22 August 2007, Pages 1934–1947