Hydrazine hydrate (1:1) → Dimethyl 4-[2-(4-aminobutoxy)-5-methylsulfonylphenyl]-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate

Participants

Reaction Steps

A solution of 6.9 g of dimethyl 4-[2-(4-phthalimidobutoxy)-5-methylsulfonylphenyl]-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate and 5.9 g of hydrazine monohydrate in 170 ml of % ethanol(water: 5%) was refluxed under heating for 6 hours. After cooling, the reaction solution was concentrated under reduced pressure. The residue was extracted with chloroform, and the extract was washed with water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. Crude crystals thus obtained were recrystallized from chloroform-ether to give 2.6 g of dimethyl 4-[2-(4-aminobutoxy)-5-methylsulfonylphenyl]-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate.

Provenance & Evidence