Isopropanol → Watanidipine

Participants

Reaction Steps

3-Nitrobenzaldehyde (1.144 g, 7.57 mmol), [p-(4-benzhydrylpiperazino)phenyl]ethyl acetoacetate (3.464 g, 7.59 mmol) and methyl 3-aminocrotonate (873 mg, 7.58 mmol) were charged in a 100 ml-eggplant type flask. Isopropanol (12 ml) was added thereto. The flask was equipped with a Dimroth condenser and refluxed under heating for 16 hours. The reaction solvent was distilled away under reduced pressure and the residue was separated by column chromatography [silica gel, chloroform--methanol (45:1)] and column chromatography [silica gel, ethyl acetate--n-hexane (2:3)], and the crude product obtained was purified by high performance liquid chromatography to give 2.503 g of the title Compound 1 (yield 48%).

Provenance & Evidence