1H-Pyrrolo[2,3-b]pyridine-2,3-dione → 1H-Pyrrolo[2,3-b]pyridine-2,3-dione 3-[O-(2-fluoro-ethyl)-oxime]
Reaktionsgleichung
[NH:1]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][N:10]=2)[C:4](=O)[C:2]1=[O:3].Cl.[F:13][CH2:14][CH2:15][O:16][NH2:17]>CS(C)=O>[F:13][CH2:14][CH2:15][O:16][N:17]=[C:4]1[C:6]2[C:11](=[N:10][CH:9]=[CH:8][CH:7]=2)[NH:1][C:2]1=[O:3]Komponenten
4
Versuchsvorschrift
A solution of compound 134a (300 mg, 1.03 mmol) in DMSO (25 mL) was heated at 95° C. at 15 torr for 6.5 hours. The solution containing the corresponding 7-aza isatin was cooled to room temperature, followed by the addition O-(2-Fluoro-ethyl)-hydroxylamine hydrochloride (131 mg, 1.13 mmol). After stirring for 1 hour at room temperature the mixture was quenched with water and extracted with ethyl acetate (6×25 mL). The combined organic phases were washed with brine and dried over MgSO4. The solvent was removed in vacuo and the residue purified by flash column chromatography (gradient, 2% MeOH in methylene chloride to 3%) to give 1H-Pyrrolo[2,3-b]pyridine-2,3-dione 3-[O-(2-fluoro-ethyl)-oxime] (200 mg, 93%) as an orange solid that was further purified by trituration from diethyl ether-methylene chloride (1:1).