反应详情

A stirred mixture of 4-[4-(5-chloro-thiophen-2-yl)-phenyl]-4-oxo-butyric acid (0.065 g, 0.00022 mol), hydroxylamine hydrochloride (0.0181 g, 0.000260 mol), sodium carbonate (0.0280 g, 0.000260 mol), and absolute ethanol was refluxed under nitrogen for 17 hours and allowed to cool. The resulting suspension was stirred at room temperature for 2 days and filtered. The filtercake was dissolved in methanol (5 mL) and water (5 mL), and the solution was filtered to remove a small amount of fines. The filtrate was acidified with 1.0 M aqueous hydrochloric acid (0.24 mL, 0.00024 mol), and the resulting suspension was rotary evaporated to remove methanol. The resulting aqueous suspension was filtered, washed with water, and dried in vacuo to give 0.0584 g of 4-[4-(5-chloro-thiophen-2-yl)-phenyl]-4-hydroxyimino-butyric acid as a pale yellow solid; mp 172-174° C.

1. temperaturewas refluxed under nitrogen for 17 hours
2. temperatureto cool
3. filtrationfiltered
4. dissolutionThe filtercake was dissolved in methanol (5 mL)
5. filtrationwater (5 mL), and the solution was filtered
6. customto remove a small amount of fines
7. customthe resulting suspension was rotary evaporated
8. customto remove methanol
9. filtrationThe resulting aqueous suspension was filtered
10. washwashed with water
11. customdried in vacuo