反应详情

温度

80 °C

To a stirred solution 5-[2-(2,4-dichloro-phenyl)-1-methyl-2-oxo-ethoxy]-3-ethyl-1H-pyrazole-4-carboxylic acid ethyl ester (2.48 g, 6.44 mmol) in 1,2-dichloroethane (40 ml) at RT is added TiCl4 (0.86 ml, 7.73 mmol). The reaction mixture is heated to 80° C. for 2 hrs. On cooling, the mixture is poured into a stirred sat. aq. NH4Cl (150 ml), (stirring continued for 5-10 mins following addition). Celite® (filter material) is added to this mixture and then filtered through a Celite® bed. The filter-cake is washed with EtOAc (30 ml) and the filtrate is extracted with EtOAc (approx. 90 ml). The combined organics are washed with 2N Na2CO3 (30 ml), brine and dried with sodium sulphate. On evaporation the resultant solid residue is triturated in 3/1 v/v iso-hexane/diethyl ether (15 ml) at RT for ½ h; the solid is filtered and dried in vacuo to give the title compound as a white solid yield: MS: m/z 367.20 [M+H]+

1. temperatureOn cooling
2. filtrationCelite® (filter material)
3. additionis added to this mixture
4. filtrationfiltered through a Celite® bed
5. washThe filter-cake is washed with EtOAc (30 ml)
6. extractionthe filtrate is extracted with EtOAc (approx. 90 ml)
7. washThe combined organics are washed with 2N Na2CO3 (30 ml), brine
8. dry with materialdried with sodium sulphate
9. customOn evaporation the resultant solid residue
10. customis triturated in 3/1 v/v iso-hexane/diethyl ether (15 ml) at RT for ½ h
11. filtrationthe solid is filtered
12. customdried in vacuo