反应详情

1.12 g (0.01 mol) of 1-ethyl-5-hydroxypyrazole is dissolved in 30 ml of t-amyl alcohol, and then 2.59 g (0.01 mol) of 4-methanesulfonyl-3-methoxymethyl-2-methylbenzoic acid, 2.06 g (0.01 mol) of N,N'-dicyclohexylcarbodiimide and 0.69 g (0.005 mol) of anhydrous potassium carbonate were sequentially added thereto. The mixture was reacted at a temperature of from 80° to 90° C. for 8 hours under stirring. After completion of the reaction, t-amyl alcohol was distilled off under reduced pressure, and 30 ml of water was added to the residue to dissolve the soluble components. The mixture was subjected to filtration to separate out the insolubles. The aqueous solution thus obtained was washed with chloroform, and concentrated hydrochloric acid was added to adjust pH<1. The precipitated oil component was extracted with chloroform. The solvent was distilled off under reduced pressure, and the residue was purified with silica gel column chromatography (eluent: ethyl acetate/ethanol=9/1) to obtain 2.3 g of the desired product. (Yield: 66%, melting point: 116°-118° C.)

1. customThe mixture was reacted at a temperature of from 80° to 90° C. for 8 hours
2. distillationwas distilled off under reduced pressure, and 30 ml of water
3. additionwas added to the residue
4. dissolutionto dissolve the soluble components
5. filtrationThe mixture was subjected to filtration
6. customto separate out the insolubles
7. customThe aqueous solution thus obtained
8. washwas washed with chloroform, and concentrated hydrochloric acid
9. additionwas added
10. extractionThe precipitated oil component was extracted with chloroform
11. distillationThe solvent was distilled off under reduced pressure
12. customthe residue was purified with silica gel column chromatography (eluent: ethyl acetate/ethanol=9/1)