Reacción #90284

Ecuación de reacción

ethyl 3-oxo-3-(2-(trifluoromethyl)pyridin-3-yl)propanoate

potassium carbonate

methylamine

1-(3,4-bis-benzyloxy-5-nitrophenyl)-2-bromo-ethanone

→

ethyl 5-(3,4-bis(benzyloxy)-5-nitrophenyl)-1-methyl-2-(2-(trifluoromethyl)pyridin-3-yl)-1H-pyrrole-3-carboxylate

Disolventes

dimethylformamide

ethanol

acetic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe reaction mixture was heated
2. 2
   Temperaturaat reflux for two hours whereupon the solvent
3. 3
   Otrowas removed by evaporation under vacuum
4. 4
   Temperaturato cool to room temperature
5. 5
   workup.ADDITIONpoured onto ice-cold 1 N aqueous hydrochloric acid (100 mL)
6. 6
   FiltraciónThe resulting precipitate was filtered off
7. 7
   Lavadowashed with water
8. 8
   Otrodried
9. 9
   OtroThe residue was chromatographed over silica gel
10. 10
    Otroevaporated

Procedimiento

To a stirred solution of methylamine (0.63 mL, 33% EtOH solution, 5 mmol) in a mixture of ethanol (25 mL) and acetic acid (0.5 mL) at room temperature was added ethyl 3-oxo-3-(2-(trifluoromethyl)pyridin-3-yl)propanoate (1.305 g, 5 mmol). The reaction mixture was heated at reflux for two hours whereupon the solvent was removed by evaporation under vacuum. To a solution of the crude product in dimethylformamide (25 mL) was added potassium carbonate (2.07 g, 15 mmol) in one portion followed by 1-(3,4-bis-benzyloxy-5-nitrophenyl)-2-bromo-ethanone (2.51 g, 5.50 mmol) and the mixture was then stirred at 100° C. Once no starting material was detectable, the reaction mixture was allowed to cool to room temperature and poured onto ice-cold 1 N aqueous hydrochloric acid (100 mL). The resulting precipitate was filtered off, washed with water and dried. The residue was chromatographed over silica gel. Homogeneous fractions were pooled and evaporated to give ethyl 5-(3,4-bis(benzyloxy)-5-nitrophenyl)-1-methyl-2-(2-(trifluoromethyl)pyridin-3-yl)-1H-pyrrole-3-carboxylate, 2.492 g (79%).

Fuente