1,2-Hydrazinedicarboxaldehyde → methyl 2-methoxy-5-(4H-triazol-4-yl)benzoate
Reaction equation
CO[C:3]1[CH:12]=[CH:11][C:10]([NH2:13])=C[C:4]=1[C:5]([O:7][CH3:8])=O.C([NH:16][NH:17]C=O)=O.O=P12OP3(OP(OP(O3)(O1)=O)(=O)O2)=O.[C:34](=O)(O)[O-].[Na+].[C:39]([O:42][CH2:43]C)(=[O:41])[CH3:40].ClCCl>CO.ClCCl>[CH3:8][O:7][C:5]1[CH:4]=[CH:3][C:12]([CH:11]2[CH:10]=[N:13][N:17]=[N:16]2)=[CH:34][C:40]=1[C:39]([O:42][CH3:43])=[O:41]Participants
Reactant 5
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 160 °C
Procedure
Alternately, according to the method of J. Med. Chem., 21, 1100 (1978), combine methyl 2-methoxy-5-aminobenzoate (1.8 g, 10 mmol), diformyl hydrazine (0.97 g, 11 mmol), and phosphorous pentoxide (1.84 g, 13 mmol). Heat to 160° C. After 1.5 hours, cool the reaction mixture and add a saturated aqueous solution of sodium bicarbonate. Extract three times with dichloromethane. Dry the combined organic layers over MgSO4, filter, and evaporate in vacuo to give a residue. Chromatograph the residue on silica gel eluting sequentially with 40% ethyl acetate/dichloromethane and then 5% methanol/dichloromethane to give methyl 2-methoxy-5-(4H-triazol-4-yl)benzoate: mp; 179-182° C. Combine methyl 2-methoxy-5-(4H-triazol-4-yl)benzoate (56 mmol) and methanol (200 mL) and water (50 mL). Add 1 M aqueous solution of sodium hydroxide (62.5 mL, 62.5 mmol). Heat to reflux. After 8 hour, concentrate in vacuo to remove most of the solvent. Adjust the pH to about 1 to 2 using a 1 M aqueous hydrochloric acid solution, extract with dichloromethane. Dry the organic layer over MgSO4, filter, and evaporate invacuo to give 2-methoxy-5-(4H-triazol-4-yl)benzoic acid.
Workup
- temperaturecool the reaction mixture
- extractionExtract three times with dichloromethane
- dry with materialDry the combined organic layers over MgSO4
- filtrationfilter
- customevaporate in vacuo
- customto give a residue
Sources & evidence
- ORD record
- ord-931ab0fbebd748e8a4e0429c9d393408
- Source dataset
- uspto-grants-1999_12
- Patent number
- US05998439
Reaction notes
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