5-Cyano-4-(3-methoxyphenyl)-2-methylthio-6-vinyl-pyrimidine (example 25a) was dissolved in a mixture of ethanol (2 ml) and toluene (2 ml). Potassium carbonate (690 mg) and diethylmalonate (272 μl) were added and the mixture was stirred at room temperature for 4 h. The reaction mixture was then poured in a mixture of 0.5M aq. HCl (25 ml) and EtOAc (50 ml). The organic layer was washed with H2O (50 ml) and sat. aq. NaCl (50 ml), dried (MgSO4) and concentrated under reduced pressure. The title compound was purified by chromatography on silica gel with toluene/EtOAC=100/0 to 95/5 (v/v) as eluent.
