反应详情

To a stirring solution of 224 mg (1.89 mmol) of thiotetronic acid in 10 mL of dimethylformamide is added 290 μL (2.08 mmol) of triethylamine and 77 mg (631 μmol) of 4-dimethylaminopyridine at 0° C. Next, 440 mg (2.29 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 530 mg (2.32 mmol) of 5-[4-(chlorophenoxy]pentanoic acid are added and the reaction mixture is stirred overnight at room temperature. The reaction is acidified with 1.0N HCl and extracted three times with ether. The combined organic layers are dried over Na2SO4 and concentrated in vacuo giving a yellow solid. The residue is recrystallized from ethyl acetate/hexane at -78° C. to give 150 mg (24%) of 4-hydroxy-3-[5-(4-chlorophenoxy)-1-oxopentyl]-2(5H)-thiophenone.

1. extractionextracted three times with ether
2. dry with materialThe combined organic layers are dried over Na2SO4
3. concentrationconcentrated in vacuo
4. customgiving a yellow solid
5. customThe residue is recrystallized from ethyl acetate/hexane at -78° C.