Ammonia → 3-cyclopropylmethyl 5-[2-(N-methyl-N-trimethylsilylmethylamino)ethyl] 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylate

Participants

Reaction Steps

A mixture of 15.3 g (53 mmol) of 2-(N-methyl-N-trimethylsilylmethylamino)ethyl acetoacetate, 13.0 g (53 mmol) of cyclopropylmethyl 2-(3-nitrobenzylidene)acetoacetate, 4.4 ml of 28% aqueous ammonia and 50 ml of ethanol was stirred at the reflux temperature for 7 hours, and then the solvent was removed under reduced pressure. The residue was chromatographed on silica gel column to afford 3-cyclopropylmethyl 5-[2-(N-methyl-N-trimethylsilylmethylamino)ethyl] 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylate (7.0 g, 25.7%) as yellow oil. Treatment of this oil with 1 equivalent of fumaric acid in ethanol gave the corresponding fumarate.

Provenance & Evidence