反应详情

5-(4-isothiazolyl)-2,4(1H,3H)-pyrimidinedione hydrochloride (Prep23, 300 mg, 1.036 mmol) was dissolved in N,N-Dimethylformamide (DMF) (4 ml) to give a pale yellow suspension. K2CO3 (215 mg, 1.554 mmol) was added ant the reaction mixture was stirred at room temperature for 1 h. 3-bromo-1,1-bis(methyloxy)propane (0.173 ml, 1.140 mmol) was added. Mixture was stirred at room temperature for 3 days, then diluted with water, acidified with diluted HCl until pH ˜5, and extracted with EtOAc. The organic phase was washed with water (3 times), brine, dried over Na2SO4, filtered and the solvent evaporated. The obtained residue was purified by flash chromatography eluting with cyclohexane/EtOAc 1:1. Obtained 60 mg (13.44% yield) of a 9:1 mixture of the title compound and the corresponding bis alkylated derivative.

1. customto give a pale yellow suspension
2. stirringMixture was stirred at room temperature for 3 days
3. extractionextracted with EtOAc
4. washThe organic phase was washed with water (3 times), brine
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. customthe solvent evaporated
8. customThe obtained residue was purified by flash chromatography
9. washeluting with cyclohexane/EtOAc 1:1
10. customObtained