Imidazole → HCID 86745239, compound

Participants

Reaction Steps

Pyridinium perbromide hydrobromide (5.6 g, 17.5 mmol) was added to a stirred ice-cooled solution of 4-(2,3-dichlorophenyl)-1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylic acid dimethylester (5.55 g, 15 mmol) and pyridine (2 g) in methylene dichloride (80ml). The solution was stirred at ice temperature for 40 minutes then washed with ice cold water (1×100 ml). The organic phase was separated and imidazole (6.8 g, 0.1 mol) added followed by anhydrous Na2SO4. After drying for 20 minutes the solution was filtered to remove NaSO4, evaporated and the residue heated on a steam bath for 40 minutes. The residue was then dissolved in EtOAc, washed with water (2×50 ml), dried, evaporated and crystallised from methyl acetate (15 ml) to give the crystalline title compound (3.34 g). This was suspended in isopropyl alcohol/methyl acetate (2:3 v/v)and acidified with ethanolic HCl to give the hydrochloride salt on cooling, m.p. 167°-170° C.

Provenance & Evidence