反应详情

To a stirred, room temperature solution of 2-(methylthio)thiazolo[5,4-b]pyridine (182 mg, 1.0 mmol) in acetic acid (10 mL) was added a solution of potassium permanganate (47.3 mg, 0.3 mmol) in water (6 mL) dropwise. The reaction mixture was stirred at room temperature for 16 h. LCMS showed incomplete conversion. Additional KMnO4 (158 mg) was mixed in and stirred for another 5 h. LCMS showed complete conversion. The reaction mixture was quenched with aqueous sodium sulfite. The resulting mixture was vigorously stirred at room temperature overnight. The resulting solution was partitioned between EtOAc and saturated Na2CO3. The aqueous layer was extracted with ethyl acetate, dried (Na2SO4), and concentrated. To the residue was added aq. Na2CO3 until the pH reaches 7. The precipitate formed was collected by filtration, dried to give 2-(methylsulfonyl)thiazolo[5,4-b]pyridine (43 mg, 0.201 mmol, 20.10% yield) as a tan solid. 1H NMR (300 MHz, CHLOROFORM-d) δ ppm 3.42 (s, 3 H) 7.62 (dd, J=8.40, 4.60 Hz, 1 H) 8.47 (dd, J=8.33, 1.46 Hz, 1 H) 8.75-8.84 (m, 1H). EST (M+1) 214.9.

1. stirringstirred for another 5 h
2. customThe reaction mixture was quenched with aqueous sodium sulfite
3. stirringThe resulting mixture was vigorously stirred at room temperature overnight
4. customThe resulting solution was partitioned between EtOAc and saturated Na2CO3
5. extractionThe aqueous layer was extracted with ethyl acetate
6. dry with materialdried (Na2SO4)
7. concentrationconcentrated
8. additionTo the residue was added aq. Na2CO3 until the pH
9. customThe precipitate formed
10. filtrationwas collected by filtration
11. customdried