Sodium hydride → Propionoxymethyl methyl 4-(2',3'-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture of 1,4-dihydro-2,6-dimethyl-4-(2',3'-dichorophenyl)-5-carboxymethyl-3-pyridinecarboxylic acid (5 g,14 mmol) and sodium hydride (0.6 g, 14 mmol) in DMF (25 ml) under nitrogen atmosphere was added chloromethyl propionate (1.71 g, 14 mmol). The reaction mixture was heated at 80° C. for 16 h. Workup by evaporation of solvent and addition of water. Extraction with dichloromethane, the extract was dried over sodium sulfate and concentrated. The resulting yellow crystals was subjected to flash chromatography [silica gel, dichloromethane - dichloromethane/methanol (9/1) gradient] to give pale yellow crystals (2.21 g, 36%), mp.123.8°-125.5° C. 1H-NMR (CDCl3): 7.30-7.03 (Ar, 3H); 5.97 (s, 1H); 5.75 (d, J=5.5 Hz, 1H); 5.72 (d, J=5.5 Hz, 1H); 5.46 (s, 1H); 3.60 (s, 3H); 2.34-2.25 (m, 8H); 1.09 (t, J=7.5 Hz, 3H). 13C-NMR (CDCl3): 173.11; 167.65; 165.83; 147.47; 146.70; 143.87; 132.86; 131.14; 129.83; 128.30; 126.96; 103.95; 101.94; 78.70; 50.92; 38.45; 27.25; 19.86; 19.25; 8.61.

Provenance & Evidence