Thymine → 1,5-Dimethyl-2,4(1H,3H)-pyrimidinedione

Temperature

60 °C

Thymine (2.0 g, 16 mmol), hexamethyl-disilazane (32 mL) and trimethyl silylchloride (4.1 mL) were added in 100 mL mad apple-type flask with a magnetic stirrer and allowed to stir for 17 hr. at 140° C. until the reaction solution became transparent. After the reaction solution was cooled to 60° C., the solution was added with methyl-iodide (10 mL) and was allowed to stir for 29 hr. at 60° C. Then, the reaction solution was added with 6 N aqueous acetic acid solution (6 mL×10) and subjected to evaporation under reduced pressure. The residues were dissolved by the addition of 2-propanol and insolubles were filtered out. The filtrate was added with ethanol-water mixture. The object was recrystallized in ethanol-water mixture to give white solids (1.6 g, yield, 72%).

1. customat 140° C.
2. stirringto stir for 29 hr
3. customat 60° C
4. customsubjected to evaporation under reduced pressure
5. dissolutionThe residues were dissolved by the addition of 2-propanol and insolubles
6. filtrationwere filtered out
7. additionThe filtrate was added with ethanol-water mixture
8. customThe object was recrystallized in ethanol-water mixture
9. customto give white
10. customsolids (1.6 g, yield, 72%)

ORD record

ord-3dc93afc4f0e48588bf358da77b0b612

Source dataset

uspto-grants-2012_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08211899B2