反应详情

To a solution of 20 g (88 mmole) of methyl 3-hydroxy-5-trifluoromethyl-2-thiophenecarboxylate in 200 mL of DMSO was added 37 g (260 mmole) of methyl iodide and 25 g (181 mmole) of powdered K2CO3. After 2 hr of stirring, the reaction mixture was poured into water and extracted with ether. The organic phase was separated, washed with water several times, dried over MgSO4, filtered and concentrated to give 20 g of a nearly colorless solid. This solid was further purified by recrystallization from 12:1 hexane:ethyl acetate to give 10.5 g of colorless crystals. The mother liquor was concentrated and purified by column chromatography to give another 8 g (87% yield). mp 78-79° C. 1H NMR (300 MHz, CDCl3): δ 7.2 (s, 1H); 4.0 (s, 3H); 3.9 (s, 3H). Anal. Calc'd for C8H7F3O3S: C, 40.00; H, 2.94; S, 13.35. Found: C, 39.87; H, 2.94; S, 13.47.

1. extractionextracted with ether
2. customThe organic phase was separated
3. washwashed with water several times
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customto give 20 g of a nearly colorless solid
8. customThis solid was further purified by recrystallization from 12:1 hexane