Salicylamide → 2,2-dimethyl-3,4-dihydro-2H-1,3-benzoxazin-4-one
Reaction equation
[C:1]([NH2:10])(=[O:9])[C:2]1[C:3](=[CH:5][CH:6]=[CH:7][CH:8]=1)[OH:4].[C:11]1(C)[CH:16]=CC(S(O)(=O)=O)=C[CH:12]=1>COC(OC)(C)C>[CH3:12][C:11]1([CH3:16])[NH:10][C:1](=[O:9])[C:2]2[CH:8]=[CH:7][CH:6]=[CH:5][C:3]=2[O:4]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
6.86 g (50 mmol) of salicylamide was suspended in 100 ml of acetone dimethylacetal. After the addition of 2.85 g (15 mmol) of p-toluenesulfonic acid, the mixture was heated to reflux for two hours. The resulting reaction mixture was evaporated under reduced pressure. After the addition of ethyl acetate, the solvent was washed twice with a saturated aqueous solution of sodium hydrogen carbonate and once with brine. The ethyl acetate layer was dried over anhydrous sodium sulfate and the solvent was removed by evaporation under reduced pressure, to obtain 8.94 g (quantitative) of the title compound as light yellow needle-like crystals.