Sodium Carbonate → 7-Fluoro-3-methyl-2,3-dihydro-4H-1,3-benzoxazin-4-one

Reaktionsgleichung

[F:1][C:2]1[CH:11]=[CH:10][C:5]([C:6]([NH:8][CH3:9])=[O:7])=[C:4]([OH:12])[CH:3]=1.[C:13](=O)([O-])[O-].[Na+].[Na+]>C=O.C(O)=O>[F:1][C:2]1[CH:11]=[CH:10][C:5]2[C:6](=[O:7])[N:8]([CH3:13])[CH2:9][O:12][C:4]=2[CH:3]=1

Komponenten

Versuchsvorschrift

A mixture of 4-fluoro-2-hydroxy-N-methyl-benzamide (0.3 g, 1.77 mmol) in formaldehyde (37% aq. soln) (2 mL) and formic acid (2 mL) was refluxed for 1 hour then poured onto ice. The mixture was neutralised with sodium carbonate and extracted into chloroform (3×30 mL). The combined organics were dried (MgSO4), and reduced in vacuo to give a white solid which was chromatographed on silica, eluting with 10-50% ethyl acetate in isohexane to give the desired compound as a white solid (0.24 g).