Reaktion #2028882

Reaktionsgleichung

aldehyde

4-[3-formyl-5-phenyl-1H-pyrazol-1-yl]benzenesulfonamide

ethyl cyanoacetate

ammonium acetate

acetic acid

→

desired product

Ausbeute 66.0%

Ethyl 3-[1-[4-(aminosulfonyl)phenyl]-5-phenyl-1H-pyrazol-3-yl]-2-cyano-2-propenoate

Ausbeute 66.0%

Lösungsmittel

benzene

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe solution was heated
2. 2
   Temperaturat reflux for 18 hours
3. 3
   Temperaturcooled
4. 4
   Sonstigepartitioned between water and ethyl acetate
5. 5
   WaschenThe organic solution was washed with a saturated aqueous sodium bicarbonate solution, water and brine
6. 6
   SonstigeThe organic solution was dried
7. 7
   Einengenconcentrated
8. 8
   SonstigeThe residue was chromatographed on silica (40% hexane in ethyl acetate)

Vorschrift

To a solution of the aldehyde from Step 1 (1.2 g, 3.6 mmol) in benzene (18 mL) was added ethyl cyanoacetate (0.38 mL, 3.6 mmol), ammonium acetate (50 mg, 0.7 mmol) and glacial acetic acid (0.17 mL, 2.8 mmol). The solution was heated at reflux for 18 hours, cooled, and partitioned between water and ethyl acetate. The organic solution was washed with a saturated aqueous sodium bicarbonate solution, water and brine. The organic solution was dried and concentrated. The residue was chromatographed on silica (40% hexane in ethyl acetate) to give the desired product (1.0 g, 66%): Anal. calc'd for C21H18N4O4S: C, 59.82; H, 4.30; N, 13.22. Found: C, 59.70; H, 4.29; N, 13.26.

Quelle