反应详情

A solution of 2.38 mL (1.1 eq) of 1N NaOH was added dropwise to a refluxing solution of 76.89 g (0.217 mole) of ethyl 5-(2,4-dichlorobenzoyl)-1,4-dimethyl-1H-pyrrole-2-acetate (3) in 750 mL absolute ethanol. The mixture was heated under reflux for 20 minutes. The reaction was poured into 3N HCl/ice and extracted three times with diethyl ether. The organics were washed with water (twice), brine, and dried (MgSO4). Evaporation of the solvent in vacuo gave a tan oil which was crystallized from acetonitrile to give 63.05 g of product: mp 140-143° C.; mass spectrum (Cl—CH4) m/z=326 (M+1); NMR 300 MHz (Me2SO-d6) d 7.8 (s, 1H); 7.6 (m, 1H); 7.4 (m, 1H); 6.0 (s, 1H); 3.8 (s, 3H); 3.75 (s, 2H); 1.45 (s, 3H). Anal Calcd for C15H13Cl2NO3: C, 55.24; H, 4.02; N, 4.29. Found: C, 55.47; H, 3.84; N, 4.29.

1. temperatureThe mixture was heated
2. temperatureunder reflux for 20 minutes
3. extractionextracted three times with diethyl ether
4. washThe organics were washed with water (twice), brine
5. dry with materialdried (MgSO4)
6. customEvaporation of the solvent in vacuo
7. customgave a tan oil which
8. customwas crystallized from acetonitrile