2-Chlorophenylhydrazine hydrochloride → HCID 59633025, compound

HRID 2369034Notes

Reaction equation

HRID 2369034 reaction equation
[CH3:1][O:2][C:3](=[O:15])[C:4](=O)[CH2:5][C:6]([C:8]1[S:9][C:10]([Br:13])=[CH:11][CH:12]=1)=O.Cl.[Cl:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][C:19]=1[NH:24][NH2:25]>CO>[CH3:1][O:2][C:3]([C:4]1[CH:5]=[C:6]([C:8]2[S:9][C:10]([Br:13])=[CH:11][CH:12]=2)[N:24]([C:19]2[CH:20]=[CH:21][CH:22]=[CH:23][C:18]=2[Cl:17])[N:25]=1)=[O:15]

Participants

4

Reactant 2

HCID 4432872-Chlorophenylhydrazine hydrochlorideHCID 59632105HCID 59632105, compound

Product 1

HCID 59633025HCID 59633025, compoundYield 100.6%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
20 °C

Procedure

A solution of 4-(5-bromo-thiophen-2-yl)-2,4-dioxo-butyric acid methyl ester (15 g, 50 mmol) and 2-chlorophenylhydrazine hydrochloride (10.75 g, 60 mmol) in dry MeOH (200 mL) was heated to reflux for 6 h. After cooling to 20° C., a white solid precipitated and was collected by filtration, washed with a small volume of cold MeOH and dried under high vacuum to afford 5-(5-bromo-thiophen-2-yl)-1-(2-chloro-phenyl)-1H-pyrazole-3-carboxylic acid methyl ester (20 g, 100%). 1H-NMR (CDCl3): δ 7.48-7.55 (m, 3H), 7.43 (m, 1H), 7.11 (s, 1H), 6.90 (d, 2H), 6.65 (s, 1H), 3.95 (s, 3H).

Workup

  1. temperatureto reflux for 6 h
  2. customa white solid precipitated
  3. filtrationwas collected by filtration
  4. washwashed with a small volume of cold MeOH
  5. customdried under high vacuum

Sources & evidence

ORD record
ord-e9ae3a8bbb4d4d41a73ad8f0bb222937
Source dataset
uspto-grants-2014_04
Patent number
US08703805B2

Reaction notes

Loading…