3-Nitrobenzaldehyde → 2-(4-Acetylaminobenzoyloxy)ethyl 2,6-dimethyl-5-ethoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

20 g (0.07 moles) of 2-(4-acetylaminobenzoyloxy)ethyl acetylacetate, 8.41 g (0.07 moles) of ethyl 3-aminocrotonate and 9.84 g (0.07 moles) of 3-nitrobenzaldehyde are heated under reflux in 65 ml of ethanol for 8 hours. The solvent is then evaporated, 15 ml of boiling methanol are added to the residue, the solution is discoloured with activated charcoal and cooled to -5° C. to obtain 2-(4-acetylaminobenzoyloxy)ethyl 2,6-dimethyl-5-ethoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylate with half a molecule of ethanol as yellow crystals melting--after recrystallisation in ethanol--at 157°-162° C. The yield is 46% of the theoretical yield.

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