Cesium carbonate → 7-Methyl-6-(methyloxy)-2H-1,4-benzoxazin-3(4H)-one

To a solution of 2-amino-5-methyl-4-(methyloxy)phenol (3.0 g, 19 mmol) in CHCl3 (100 mL) were added saturated NaHCO3 (60 mL) and bromoacetyl bromide (5.78 g, 28.5 mmol) sequentially. The reaction mixture was vigorously stirred for 2 hours at room temperature, diluted with EtOAc (300 mL), washed with H2O, brine, and dried (Na2SO4). The solvent was removed via rotovap to give a brown solid. This brown solid was dissolved in DMF (200 mL), Cs2CO3 (6.19 g, 19 mmol) was added, and the reaction mixture was heated at 80° C. for 3 h. It was then poured into cold water (300 mL) and extracted with EtOAc (3×250 mL). The organic extracts were combined, washed with water, brine, and dried (MgSO4). The solvent was removed via rotovap, and the residue was purified on silica gel, using 50% EtOAc-Hexane, to give the title compound (2.13 g, 58%) as a brown solid. MS (ES) m/e 194 [M+H]+.

1. washwashed with H2O, brine
2. dry with materialdried (Na2SO4)
3. customThe solvent was removed via rotovap
4. customto give a brown solid
5. temperaturethe reaction mixture was heated at 80° C. for 3 h
6. extractionextracted with EtOAc (3×250 mL)
7. washwashed with water, brine
8. dry with materialdried (MgSO4)
9. customThe solvent was removed via rotovap
10. customthe residue was purified on silica gel

ORD record

ord-fec10780722348eabdc8862989446124

Source dataset

uspto-grants-2010_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07749998B2