Diisobutylaluminumhydride → methyl 2-bromo-3-(2-butyn-1-yl)-5-formyl-3H-imidazole-4-carboxylate
Reaktionsgleichung
[H-].C([Al+]CC(C)C)C(C)C.[Br:11][CH:12]1[N:16]([CH2:17][C:18]#[C:19][CH3:20])[C:15]([C:21]([O:23][CH3:24])=[O:22])=[C:14]([C:25](OC)=[O:26])[NH:13]1>O1CCCC1>[Br:11][C:12]1[N:16]([CH2:17][C:18]#[C:19][CH3:20])[C:15]([C:21]([O:23][CH3:24])=[O:22])=[C:14]([CH:25]=[O:26])[N:13]=1Komponenten
Reaktionsbedingungen
- Temperatur
- -65 °C
Versuchsvorschrift
45 ml diisobutylaluminum hydride solution (1M in toluene) are added dropwise to 12.45 g dimethyl 2-bromo-3-(2-butyn-1-yl)-1H-imidazole-4,5-dicarboxylate in 150 ml of tetrahydrofuran under an argon atmosphere at −65° C. The reaction mixture is stirred for two hours at −65° C., then another 9 ml diisobutylaluminum hydride solution are added. After another hour the reaction mixture is quenched at −65° C. with a mixture of 1 M hydrochloric acid and tetrahydrofuran (1:1) and stirred for ten minutes. Then the cooling bath is removed, the reaction mixture is diluted with water and extracted with ethyl acetate. The combined organic phases are dried over magnesium sulphate and evaporated down. The crude product is purified by chromatography over a silica gel column with cyclohexane/ethyl acetate (2:1 to 1:1).
Aufarbeitung
- customAfter another hour the reaction mixture is quenched at −65° C. with a mixture of 1 M hydrochloric acid and tetrahydrofuran (1:1)
- stirringstirred for ten minutes
- customThen the cooling bath is removed
- additionthe reaction mixture is diluted with water
- extractionextracted with ethyl acetate
- dry with materialThe combined organic phases are dried over magnesium sulphate
- customevaporated down
- customThe crude product is purified by chromatography over a silica gel column with cyclohexane/ethyl acetate (2:1 to 1:1)
Quellen und Nachweise
- ORD-Eintrag
- ord-37d8f047297e4e94ac62c04efc8561b7
- Quelldatensatz
- uspto-grants-2011_10
- Patentnummer
- US08034941B2
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