3-Nitrobenzaldehyde → 2,6-Dimethyl-3,5-di(2-phthalimidocarbethoxy)-4-(3-nitrophenyl)-1,4-dihydropyridine

Participants

Reaction Steps

A solution of 137 mg (0.9 m mol) of 3-nitrobenzaldehyde, 0.5 g (1.82 m mol) of 2-phthalimidoethyl acetoacetate, and 0.16 ml (2.4 m mol) of 14.7M ammonium hydroxide in 40 ml of 2-propanol was refluxed for 15 hours under nitrogen. The solvent was removed in vacuo and the residue was subjected to flash chromatography (silica gel, 3:1 petroleum ether/ethyl acetate) to yield 50 mg of pale yellow product; m.p. 92°-94° C.; NMR: (CDCl3) δ2.2 (6M,s), 3.8 (4H,m), 4.2 (4H,m), 4.8 (1H,s), 6.1 (1H,s), 7.2 (12H,m).

Provenance & Evidence