反应详情

Sodium methylate (17 g) was dissolved in methanol (600 ml) at 0° C. 2-p-tolyl-malonic acid diethyl ester (24.5 ml, commercially available from Aldrich), dissolved in 150 ml methanol, was added within 30 min. Stirring was continued for 1 h while slowly warming the mixture to rt. Formamidine hydrochloride (9.9 g, commercially available from Fluka) was added and stirring was continued for 16 h. The solvent was evaporated and 2 M hydrochloric acid (200 ml) was added to the residue followed by slow addition of 10 M sodium hydroxide to adjust the pH to 5. The precipitated product was filtered off and washed subsequently with water and diethylether and dried to give 5-p-tolyl-pyrimidine-4,6-diol (17.7 g). 1H-NMR (300 MHz, d6-DMSO): 8.0(s, 1H); 7.4(d, 2H); 7.1(d, 2H); 2.25(s, 3H).

1. additionwas added within 30 min
2. stirringstirring
3. waitwas continued for 16 h
4. customThe solvent was evaporated
5. addition2 M hydrochloric acid (200 ml) was added to the residue
6. additionfollowed by slow addition of 10 M sodium hydroxide
7. filtrationThe precipitated product was filtered off
8. washwashed subsequently with water and diethylether
9. customdried