Reaktionsgleichung
[CH2:1]([O:3][C:4]([C:6]1[N:7]=[C:8]([SH:11])[S:9][CH:10]=1)=[O:5])[CH3:2].[H-].[Na+].Br[CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][CH3:22].O>CN(C=O)C>[CH2:1]([O:3][C:4]([C:6]1[N:7]=[C:8]([S:11][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][CH3:22])[S:9][CH:10]=1)=[O:5])[CH3:2]Komponenten
Edukt 4
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
To a solution of 2-mercaptothiazole-4-carboxylic acid ethyl ester (Zhelyazkov, L.; Todorova, N.; Manolova, P. Tr. Nauchnoizsled. Khim.-Farm. Inst., 9, 59-67 (1974); Chem. Abstr., 83, 58706 q) (3.0 g) in DMF (20 ml) is added sodium hydride (0.70 g of 60% dispersion). After 10 min, 1-bromooctane (3.0 ml) is added, and the mixture is stirred at 60° for 30 min. The mixture is poured into water and extracted with ether, and the extracts are dried, filtered, and concentrated. The residue is recrystallized from hexane to provide 2-(octylthio)thiazole-4-carboxylic acid ethyl ester as a colorless solid (3.7 g, 78%). This material is reduced in the usual fashion with lithium aluminum hydride in THF, providing 2-(octylthio)thiazole-4-methanol (2.12 g, 67%) as a colorless oil after chromatography. This is combined with DDQ (1.8 g) in 1,4-dioxane (25 ml) and stirred for 48 hr at room temperature. The reaction mixture is filtered, and the filtrate is concentrated and chromatographed with dichloromethane to provide 2-(octylthio)thiazole-4-carboxaldehyde as a tan solid (1.67 g, 81%).
Aufarbeitung
- extractionextracted with ether
- customthe extracts are dried
- filtrationfiltered
- concentrationconcentrated
- customThe residue is recrystallized from hexane
Quellen und Nachweise
- ORD-Eintrag
- ord-98e1c24e5a604cc69a49499f9b1264e5
- Quelldatensatz
- uspto-grants-1995_11
- Patentnummer
- US05464865
Verknüpfte Notizen
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