Dimethyl Sulfide → 7-Chloro-3-oxo-3,4-dihydro-2H-pyrido[3,2-b][1,4]oxazine-6-carbaldehyde

Temperature

-78 °C

7-Chloro-6-((E)-styryl)-4H-pyrido[3,2-b][1,4]oxazin-3-one (8.0 g, 27.9 mmole) was dissolved in a mixture of DMF (400 mL) and methanol (40 mL), and the solution was cooled to −78° C. Ozone was bubbled through the solution with stirring for 45 minutes, then the excess ozone was removed by bubbling oxygen through the solution for 30 min. Dimethylsulfide (21 mL, 279 mmole) was added to the solution, and the reaction was stirred at −78° C. for 3 hr, then at room temperature overnight. The solvent was removed in vacuo, and the residue was triturated with Et2O (150 mL). The collected solid was washed with additional Et2O and dried to afford a white solid (4 g, 68%).

1. customOzone was bubbled through the solution
2. customthe excess ozone was removed
3. customby bubbling oxygen through the solution for 30 min
4. stirringthe reaction was stirred at −78° C. for 3 hr
5. customat room temperature
6. customovernight
7. customThe solvent was removed in vacuo
8. customthe residue was triturated with Et2O (150 mL)
9. washThe collected solid was washed with additional Et2O
10. customdried

ORD record

ord-fc22bd498b15429ba53c6cfc43e6e3a8

Source dataset

uspto-grants-2010_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07691850B2