5-Methoxyanthranilic acid → 2-Carboxy-4-methoxyphenylhydrazine

HRID 649816Notes

Reaction equation

HRID 649816 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:9]([NH2:12])=[CH:10][CH:11]=1)[C:6]([OH:8])=[O:7].[N:13]([O-])=O.[Na+].Cl[Sn]Cl.O>Cl.O>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:9]([NH:12][NH2:13])=[CH:10][CH:11]=1)[C:6]([OH:8])=[O:7]

Participants

6

Reactant 3

HCID 2779305-Methoxyanthranilic acidHCID 23668193Sodium NitriteHCID 43835034Tin dichloride dihydrate

Product 1

HCID 129676382-Carboxy-4-methoxyphenylhydrazineYield 284%

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolvent2×HCID 962WaterSolvent

Procedure

Part A: 5-(Furan-2-yl)-3-trifluoromethyl-1-(2-carboxyl-4-methoxyphenyl)-1H-pyrazole: 3-Methoxy-6-aminobenzoic acid (23 g, 138 mmol) in conc. HCl (300 mL) was cooled to 0° C. and NaNO2 (11.4 g, 165 imnol) in H2O (50 mL) was added dropwise while the temperature of the reaction was maintained below 10° C. The reaction was stirred at or below 10° C. for 1 h, then SnCl2.H2O (92.3 g, 413 mmol) in conc. HCl (125 mL) was added dropwise. The reaction was allowed to thaw to ambient temperature and stirred for 3 h. The precipitate was filtered and air-dried then heated in a vacuum oven for 18 h. There was obtained 71.4 g of 3-methoxy-6-hydrazinobenzoic acid entrained with tin (II) salts.

Workup

  1. temperaturewas maintained below 10° C
  2. customthaw to ambient temperature
  3. stirringstirred for 3 h
  4. filtrationThe precipitate was filtered
  5. customair-dried
  6. temperaturethen heated in a vacuum oven for 18 h

Sources & evidence

ORD record
ord-61d8b69c398a49c584b58e9c0aaf596c
Source dataset
uspto-grants-2001_08
Patent number
US06271237B1

Reaction notes

Loading…