methyl 4-(4-chlorophenyl)-2,4-dioxobutanoate → methyl 1-[4-(aminosulfonyl)phenyl]-5-(4-chlorophenyl)-1H-pyrazole-3-carboxylate

HRID 2084706Notes

Reaction equation

HRID 2084706 reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([C:8](=O)[CH2:9][C:10](=O)[C:11]([O:13][CH3:14])=[O:12])=[CH:4][CH:3]=1.[CH:17]1[C:22]([NH:23][NH2:24])=[CH:21][CH:20]=[C:19]([S:25]([NH2:28])(=[O:27])=[O:26])[CH:18]=1.Cl>CO>[NH2:28][S:25]([C:19]1[CH:18]=[CH:17][C:22]([N:23]2[C:8]([C:5]3[CH:6]=[CH:7][C:2]([Cl:1])=[CH:3][CH:4]=3)=[CH:9][C:10]([C:11]([O:13][CH3:14])=[O:12])=[N:24]2)=[CH:21][CH:20]=1)(=[O:27])=[O:26]

Participants

4

Reactant 2

HCID 308124methyl 4-(4-chlorophenyl)-2,4-dioxobutanoateHCID 27945674-Hydrazinylbenzenesulfonamide hydrochloride

Product 1

HCID 3289819methyl 1-[4-(aminosulfonyl)phenyl]-5-(4-chlorophenyl)-1H-pyrazole-3-carboxylateYield 97%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
0 °C

Procedure

A 100 mL round-bottomed flask equipped with magnetic stirrer and nitrogen inlet was charged with methyl 4-[4-(chloro)phenyl]-2,4-dioxobutanoate from Step 1 (5.0 g, 20.78 mmol), 4-sulfonamidophenylhydrazine hydrochloride (5.11 g, 22.86 mmol) and methanol (50 mL). The reaction vessel was heated to reflux and held for 16 hours. A precipitate formed overnight. The suspension was cooled to 0° C., held for 0.5 hour, filtered and washed with cold water to provide, after air-drying, 7.91 g (91%) of crude product. Recrystallized 3.50 g from boiling ethanol to yield 3.14 g (97% of pure methyl (1-(4-aminosulfonylphenyl)-5-(4-chlorophenyl)-1H-pyrazole-3-yl]carboxylate: mp 227° C.; 1H NMR (CDCl3/300 MHz); 7.91 (d, J=8.86 Hz, 2H), 7.44 (d, J=8.86 Hz, 2H), 7.33 (d, J=8.66 Hz, 2H), 7.14 (d, J=8.66 Hz, 2H), 7.03 (s, 1H), 3.96 (s, 3H). Mass Spectrum, MH+=392. Anal. Calc'd for C17H14N3O4ClS: C, 52.11; H, 3.60; N, 10.72; Cl, 9.05; S, 5.18. Found: C, 52.07; H, 3.57; N, 10.70; Cl, 9.11; S, 8.27.

Workup

  1. customA 100 mL round-bottomed flask equipped with magnetic stirrer and nitrogen inlet
  2. temperatureThe reaction vessel was heated
  3. temperatureto reflux
  4. customA precipitate formed overnight
  5. waitheld for 0.5 hour
  6. filtrationfiltered
  7. washwashed with cold water
  8. customto provide
  9. customafter air-drying
  10. customRecrystallized 3.50 g

Sources & evidence

ORD record
ord-6220df667b264bd8bf4232a3ee3826fa
Source dataset
uspto-grants-2004_04
Patent number
US06716991B1

Reaction notes

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