Pyridine → HCID 20070377, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-2-[2-(2,4,5-trimethylimidazol-1-yl)ethoxymethyl]-1,4-dihydropyridine (3.0 g) in chloroform (50 cm3) stirred at 0° C. under N2 was treated with pyridine (790 mg) followed by pyridinium bromide perbromide (2.1 g) in portions over five minutes and the mixture stirred at 0° C. for one hour and then heated at reflux temperature for three hours. The solution was cooled, washed with 2N hydrochloric acid (2×50 cm3) and brine (50 cm3), dried over MgSO4, filtered and evaporated to dryness. The residue was purified by silica-gel column chromatography eluting with diethylamine/ethyl acetate (1:9). The appropriate fractions were evaporated to dryness and taken up in ethyl acetate (25 cm3) from which the title compound crystallised as a colourless solid (440 mg). M.p. 215°-217° C.

Provenance & Evidence