Réaction #58680

Équation de réaction

4-Chlorophenylhydrazine hydrochloride

di-isopropylethylamine

Isatoic anhydride

→

2-amino-benzoic acid N′-(4-chloro-phenyl)-hydrazide

Rendement 50.0%

Solvants

EtOH

Conditions de réaction

Traitement

1. 1
   Températurethe mixture was heated
2. 2
   Températureto reflux for 3 hours
3. 3
   workup.STIRRINGstirred overnight
4. 4
   ConcentrationThe material was concentrated to dryness
5. 5
   Autrethe resulting residue was partitioned between EtOAc (˜25 ml) and 50% saturated NaCl (3×30 ml)
6. 6
   workup.ADDITIONThe organic layer (also containing a small amount of emulsion which would not
7. 7
   Extractiondissipate over 3 extractions)
8. 8
   Séchagewas dried over MgSO4
9. 9
   Concentrationconcentrated to an orange solid
10. 10
    AutreThe material was triturated with EtOAc
11. 11
    Filtrationfiltered
12. 12
    Lavagerinsed with additional EtOAc
13. 13
    ConcentrationThe filtrate was concentrated to dryness
14. 14
    workup.ADDITIONtreated with DCM (dichloromethane)
15. 15
    workup.STIRRINGThe mixture was stirred overnight
16. 16
    FiltrationThe mixture was filtered
17. 17
    Lavagerinsed with DCM
18. 18
    Autrethe solid dried

Mode opératoire

4-Chlorophenylhydrazine hydrochloride (2.105 g, 14.76 mmol) was suspended in EtOH (25 ml), treated with di-isopropylethylamine (2.253 ml, 12.93 mmol) and stirred for 30 minutes. Isatoic anhydride (1.918 g, 11.76 mmol) was added and the mixture was heated to reflux for 3 hours. The reaction mixture was cooled to room temperature and stirred overnight. The material was concentrated to dryness and the resulting residue was partitioned between EtOAc (˜25 ml) and 50% saturated NaCl (3×30 ml). The organic layer (also containing a small amount of emulsion which would not dissipate over 3 extractions) was dried over MgSO4 and concentrated to an orange solid. The material was triturated with EtOAc, filtered and rinsed with additional EtOAc. The filtrate was concentrated to dryness and treated with DCM (dichloromethane). The mixture was stirred overnight. The mixture was filtered, rinsed with DCM and the solid dried to provide 1.538 g (50%) of 2-amino-benzoic acid N′-(4-chloro-phenyl)-hydrazide (Intermediate 40) as a mauve-colored solid. MS (APCI): (M+1)=262.1, (M−1)=260.0.

Source