1,3-Dimethyl 2-(4-chlorophenyl)propanedioate → 5-(4-Chlorophenyl)pyrimidine-4,6-diol

Beteiligte Stoffe

Reaktionsschritte

A solution of 2-(4-chlorophenyl)-malonic acid dimethyl ester (18.90 g) in methanol (200 ml) was added dropwise at 0° C. to a solution sodium methylate (14.60 g) in methanol (150 ml). The mixture was stirred for 1 h at 0° C. before formamidine hydrochloride (7.66 g) was added. The suspension was stirred at rt for 20 h. The solvent was removed and the residue was suspended in 2 N aq. HCl (200 ml). The pH of the suspension was carefully adjusted to 4–5 by adding 10 M NaOH (20 ml), stirring was continued for 30 min. The white precipitate was collected, washed with water and diethyl ether and dried to give 5-(4-chlorophenyl)-pyrimidine-4,6-diol (16.44 g) as a white powder. LC-MS: tR=2.75 min, [M+H]+=222.96, [M−H]−=220.92.

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