反应详情

To a vigorously stirred solution of tert-butyl 3-bromo-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazine-7(8H)-carboxylate (1.0 g, 3.3 mmol) in 1:1 CHCl3:MeCN (25 mL) was added ruthenium (IV) oxide hydrate (65 mg, 0.43 mmol) and sodium metaperiodate (3.3 g, 15.5 mmol) in water (31 mL). After 1 h, additional ruthenium (IV) oxide hydrate (50 mg) was added. After another hour, a final portion of ruthenium (IV) oxide hydrate (30 mg) was added. Stirring was maintained for 30 minutes and then water was added. The entire mixture was extracted with CHCl3. The combined organic extracts were dried (Na2SO4), filtered, and concentrated to afford a green oil. Purification by chromatography (SiO2; hexanes—100% EtOAc) provided the desired product as a white solid (663 mg, 63%). MS (ESI): mass calcd. for C10H13BrN4O3, 316.0; m/z found, 317.0 [M+H]+. 1H NMR (400 MHz, CDCl3) δ 4.41-4.28 (m, 2H), 4.26-4.22 (m, 2H), 1.58 (s, 9H).

1. waitAfter another hour
2. temperaturewas maintained for 30 minutes
3. extractionThe entire mixture was extracted with CHCl3
4. dry with materialThe combined organic extracts were dried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customto afford a green oil
8. customPurification by chromatography (SiO2; hexanes—100% EtOAc)