2-Chlorophenylhydrazine hydrochloride → HCID 59632248, compound

HRID 2369092Notes

Reaction equation

HRID 2369092 reaction equation
Cl.[Cl:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[NH:9][NH2:10].[Br:11][C:12]1[CH:13]=[CH:14][C:15]([C:18](=O)[CH2:19][C:20](=O)[C:21]([O:23][CH3:24])=[O:22])=[N:16][CH:17]=1.C([O-])(O)=O.[Na+]>CO.CCOC(C)=O>[Br:11][C:12]1[CH:13]=[CH:14][C:15]([C:18]2[N:9]([C:4]3[CH:5]=[CH:6][CH:7]=[CH:8][C:3]=3[Cl:2])[N:10]=[C:20]([C:21]([O:23][CH3:24])=[O:22])[CH:19]=2)=[N:16][CH:17]=1

Participants

6

Reactant 3

HCID 4432872-Chlorophenylhydrazine hydrochlorideHCID 516892Sodium BicarbonateHCID 59633371HCID 59633371, compound

Product 1

HCID 59632248HCID 59632248, compoundYield 13%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
120 °C

Procedure

A mixture of (2-chlorophenyl)hydrazine hydrochloride (1.1 g, 6.1 mmol) and methyl 4-(5-bromopyridin-2-yl)-2,4-dioxobutanoate (1.7 g, 6.0 mmol) in MeOH (30 mL) was divided into two microwave reaction vessels. Each reaction vessel was then heated in the microwave at 120° C. for ten minutes. LC/MS analysis at this time showed the reaction to be essentially complete. The solutions were concentrated under reduced pressure to afford a dark brown semi-solid. This material was taken up in EtOAc and saturated aqueous NaHCO3. The layers were separated and the basic aqueous was extracted with EtOAc (3×). Combined organic extracts were washed with brine, dried over Na2SO4, filtered and concentrated to afford a dark oil. This crude product was purified by flash column chromatography eluting with a gradient from 0% to 100% EtOAc in hexane to afford methyl 5-(5-bromopyridin-2-yl)-1-(2-chlorophenyl)-1H-pyrazole-3-carboxylate (300 mg, 13% yield) as an oil.

Workup

  1. customwas divided into two microwave reaction vessels
  2. customthe reaction
  3. concentrationThe solutions were concentrated under reduced pressure
  4. customto afford a dark brown semi-solid
  5. customThe layers were separated
  6. extractionthe basic aqueous was extracted with EtOAc (3×)
  7. washCombined organic extracts were washed with brine
  8. dry with materialdried over Na2SO4
  9. filtrationfiltered
  10. concentrationconcentrated
  11. customto afford a dark oil
  12. customThis crude product was purified by flash column chromatography
  13. washeluting with a gradient from 0% to 100% EtOAc in hexane

Sources & evidence

ORD record
ord-7e85f800326a44cb9052621485800615
Source dataset
uspto-grants-2014_04
Patent number
US08703805B2

Reaction notes

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