[Br:1][C:2]1[CH:6]=[CH:5][S:4][C:3]=1[C:7]([NH2:9])=O.COC(OC)[N:13]([CH3:15])C.C1(C)C=CC=CC=1.C(O)(=O)C.[NH2:29]N>>[Br:1][C:2]1[CH:6]=[CH:5][S:4][C:3]=1[C:7]1[NH:9][CH:15]=[N:13][N:29]=13-Bromothiophene-2-carboxamide (33.2 g, 161 mmol) in 1,1-dimethoxy-N,N-dimethylmethanamine (100 mL, 800 mmol) and toluene (100 mL, 900 mmol) was heated at 90° C. for 2 h. The solvent was evaporated off and the residue was dissolved in acetic acid (183 mL, 3220 mmol). Hydrazine (20 mL, 600 mmol) was added and the mixture was heated at 90° C. again. After 40 min, LCMS showed complete reaction. The reaction mixture was evaporated to remove most of the acetic acid. Water was added and the precipitate was collected and dried in air overnight to afford 3-(3-bromothiophen-2-yl)-4H-1,2,4-triazole as a white powder (31.7 g, 85.6%). LCMS: (FA) ES+ 230.0, 232.0
Wird geladen…
