Cyclopentyl 2-(2,3-dichlorophenylmethylene)-3-oxobutanoate → 5-Cyclopentyl 3-methyl 4-(2,3-dichlorophenyl)-2-(fluoromethyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate

Participants

Reaction Steps

A solution of the product of step (a) (5.1 g, 14.3 mmoles) and methyl 3-amino-4-fluoro-2-butenoate (1.9 g, 14.3 mmoles) in dry tert-butanol (25 ml) was heated to 60° (oil bath temperature) for 108 hours. The solution was allowed to cool to room temperature and the solvent removed in vacuo. Chromatography on silica eluting with dichloromethane afforded the title compound as a yellow oil which crystallises on addition of petroleum ether (60°-80° ) to afford the title compound 1.5 g mp 148°-9°. (Identical with the product of Example 3).

Provenance & Evidence