2-(Ethoxymethylene)propanedinitrile → 5-amino-1-(2,3-dichlorophenyl)-1H-pyrazole-4-carbonitrile

HRID 1098235Notes

Reaction equation

HRID 1098235 reaction equation
Cl.[Cl:2][C:3]1[C:8]([Cl:9])=[CH:7][CH:6]=[CH:5][C:4]=1[NH:10][NH2:11].C(O[CH:15]=[C:16]([C:19]#[N:20])[C:17]#[N:18])C.ClC1C(Cl)=CC=CC=1NN>CO>[NH2:20][C:19]1[N:10]([C:4]2[CH:5]=[CH:6][CH:7]=[C:8]([Cl:9])[C:3]=2[Cl:2])[N:11]=[CH:15][C:16]=1[C:17]#[N:18]

Participants

5

Reactant 3

HCID 671522-(Ethoxymethylene)propanedinitrileHCID 600691(2,3-Dichlorophenyl)hydrazineHCID 122765722,3-Dichlorophenylhydrazine HCl

Product 1

HCID 27972505-amino-1-(2,3-dichlorophenyl)-1H-pyrazole-4-carbonitrileYield 100%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

(2,3-Dichlorophenyl)hydrazine hydrochloride (CAS no. 21938-47-6) (6.06 g, 28.4 mmol) was partitioned between EtOAc and 2M NaOH. Separated. The organic solution was dried (MgSO4), filtered and reduced to give the free base. 2-(Ethoxymethylene)malononitrile (3.47 g, 28.39 mmol) was added portionwise to a stirred solution of (2,3-dichlorophenyl)hydrazine in MeOH (50 mL), under nitrogen at 5° C. The resulting solution was allowed to stir for a further 1 hour. The reaction mixture was then heated to reflux and was stirred for 3 hours. The reaction mixture was allowed to cool to ambient temperature, then was evaporated to afford the product (7.19 g, 100%) which was used without further purification. 1H NMR (400 MHz, DMSO) δ 6.75 (2H, s), 7.48-7.53 (2H, m), 7.77 (1H, s), 7.79-7.84 (1H, m).

Workup

  1. custom21938-47-6) (6.06 g, 28.4 mmol) was partitioned between EtOAc and 2M NaOH
  2. customSeparated
  3. dry with materialThe organic solution was dried (MgSO4)
  4. filtrationfiltered
  5. customto give the free base
  6. temperatureThe reaction mixture was then heated
  7. temperatureto reflux
  8. stirringwas stirred for 3 hours
  9. customwas evaporated

Sources & evidence

ORD record
ord-5d164f5faced4fa98ede5f335c4876e9
Source dataset
uspto-grants-2012_03
Patent number
US08143263B2

Reaction notes

Loading…