A suspension of 1-(4-n-pentyloxyphenyl)acrolein (2.38 g), methyl 4-formylbenzoate (1.97 g), 3-benzyl-5-(2-hydroxyethyl)-4-methylthiazolium chloride and triethylamine (0.91 ml) in ethanol (10 ml) was refluxed for 18 hours. After cooling, the solvents were removed under reduced pressure. The solids were taken up in 1N HCl and extracted with dichloromethane. The organic layer was washed successively with water and brine, dried over magnesium sulfate and evaporated under reduced pressure. The residue was triturated with diisopropyl ether, collected by filtration and dried under reduced pressure to give 1-(4-methoxycarbonylphenyl)-4-(4-n-pentyloxyphenyl)butane-1,4-dione (3.41 g).
