Cesium carbonate → 5-Benzyloxycarbonylmethoxy-1-phenyl-1H-pyrazole-3-carboxylic acid ethyl ester

반응식

[CH2:1]([O:3][C:4]([C:6]1[CH:10]=[C:9]([OH:11])[N:8]([C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[N:7]=1)=[O:5])[CH3:2].Br[CH2:19][C:20]([O:22][CH2:23][C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1)=[O:21].C(=O)([O-])[O-].[Cs+].[Cs+]>CN(C=O)C>[CH2:1]([O:3][C:4]([C:6]1[CH:10]=[C:9]([O:11][CH2:19][C:20]([O:22][CH2:23][C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)=[O:21])[N:8]([C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[N:7]=1)=[O:5])[CH3:2]

참가 물질

실험 절차

To a solution of 10.0 g 5-hydroxy-1-phenyl-1H-pyrazole-3-carboxylic acid ethyl ester in 100 ml DMF were added 7.1 ml benzyl bromoacetate and 24.0 g cesium carbonate. After stirring for 16 h at RT the suspension was filtered, washed with DMF and concentrated. The residue was taken up with ethyl acetate and extracted with aqueous LiCl (4%). Evaporation of the solvent yielded the crude product which was used in the subsequent debenzylation. Yield: 15.5 g yellow oil.