Water → 1H-Benzimidazole-4-carbohydrazide
Reaction equation
C[O:2][C:3]([C:5]1[C:10]2[N:11]=[CH:12][NH:13][C:9]=2[CH:8]=[CH:7][CH:6]=1)=O.O.[NH2:15][NH2:16].O>CCO>[N:11]1[C:10]2[C:5]([C:3]([NH:15][NH2:16])=[O:2])=[CH:6][CH:7]=[CH:8][C:9]=2[NH:13][CH:12]=1Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
Benzimidazole ester 3 (1.65 g, 9.36 mmol), hydrazine monohydrate (10 mL), and water (3 mL) were refluxed in EtOH (60 mL) for 24 hs. Reaction mixture was cooled to room temperature and solid formed was filtered, washed with EtOH and dried to give 1.13 g (68%) of pure 4: 1H NMR (DMSO-d6) δ 12.31 (br.s, 1H), 10.59 (s, 1H), 8.44 (s, 1H), 7.86 (d, 1H, J=6.5 Hz), 7.76 (d, 1H, J=8.0 Hz), 7.34 (t, 1H, J=8.0 Hz), 4.68 (s, 2H).
Workup
- customReaction mixture
- customsolid formed
- filtrationwas filtered
- washwashed with EtOH
- customdried
- customto give 1.13 g (68%) of pure 4
Sources & evidence
- ORD record
- ord-6a4dd83572c947db8f9a9740f2244af9
- Source dataset
- uspto-grants-2007_06
- Patent number
- US07235557B2
Reaction notes
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