Hydrazine hydrate (1:1) → 4-(Pyridin-2-yl)benzaldehyde hydrazone
Reaction equation
O.[NH2:2][NH2:3].[N:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1[C:10]1[CH:17]=[CH:16][C:13]([CH:14]=O)=[CH:12][CH:11]=1>CO>[N:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1[C:10]1[CH:17]=[CH:16][C:13]([CH:14]=[N:2][NH2:3])=[CH:12][CH:11]=1Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a mixture of 80% hydrazine hydrate (1.64 g, 26.2 mmol) and methanol (5.0 ml) was dropwise added a solution of 4-(pyridin-2-yl)benzaldehyde (1.5 g, 8.2 mmol) in methanol (5.0 ml) at 25° C. over 10 minutes. After the dropwise addition, the mixture was stirred for 30 minutes. Methanol and excess hydrazine hydrate were evaporated under reduced pressure. The residue was crystallized and 4-(pyridin-2-yl)benzaldehyde hydrazone was obtained as crude crystals at a yield of 1.6 g (yield: 100%). The percentage of the area of 4-(pyridin-2-yl)benzaldehyde hydrazone in the crude crystals as determined by liquid chromatography was 94.3%. crude crystals melting point: 65.7-67.8° C. IR(KBr)cm−1: 3700-3000, 1636, 1590, 1468, 1432, 1394, 1150, 1114, 924, 840, 778, 742, 726. 1H-NMR(CDCl3) δ: 5.60(s,2H), 7.22(m,1H), 7.65(d,2H), 7.74(m,2H), 7.78(s,1H), 8.00(d,2H), 8.69(d,1H)
Workup
- additionAfter the dropwise addition
- customMethanol and excess hydrazine hydrate were evaporated under reduced pressure
- customThe residue was crystallized
Sources & evidence
- ORD record
- ord-4c47f6d5a3734780ac1a50d9c7a62691
- Source dataset
- uspto-grants-2001_07
- Patent number
- US06268503B1
Reaction notes
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