[CH3:1][C:2]1[CH:6]=[CH:5][N:4]([CH2:7][C:8]([OH:10])=[O:9])[N:3]=1.OS(O)(=O)=O.[CH3:16][CH2:17]O>C(Cl)Cl>[CH3:1][C:2]1[CH:6]=[CH:5][N:4]([CH2:7][C:8]([O:10][CH2:16][CH3:17])=[O:9])[N:3]=1A suspension of (3-methyl-1H-pyrazol-1-yl)acetic acid (200 mg) and H2SO4 (0.1 mL) in EtOH (2 mL) was stirred at 80° C. for 4 h. After cooling down, the reaction mixture was diluted with DCM and washed with sat. Na2CO3, water and brine. The aq. layers were extracted with DCM, the combined org. layers were dried (MgSO4), filtered off and evaporated in vacuo to afford ethyl 2-(3-methyl-1H-pyrazol-1-yl)acetate (101 mg, colourless liquid). LC-MS (B): tR=0.57 min; [M+H]+: 169.01.
Wird geladen…