Ethanol → Amlodipine Maleate

Participants

Reaction Steps

A suspension of 2-(2-azidoethoxymethyl)-4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-1,4-dihydropyridine (103 g) in ethanol (2.5 l) was stirred for 16 hours at room temperature under one atmosphere of hydrogen in the presence of 5% palladium on calcium carbonate (40 g). The reaction mixture was filtered and evaporated and the residue treated with a solution of maleic acid (22 g) in ethanol (100 ml). The reaction mixture was stirred at room temperature for 2 hours and then the resulting solid collected, washed with ethanol, and dried to give the title compound (100 g), m.p. 169°-170.5°.

Provenance & Evidence