Acetyl chloride → 7-Methoxyisochroman-1,3-dione
Reaktionsgleichung
[C:1]([CH2:4][C:5]1[CH:13]=[CH:12][C:11]([O:14][CH3:15])=[CH:10][C:6]=1[C:7]([OH:9])=[O:8])(O)=[O:2].C(Cl)(=O)C>CC(C)=O>[CH3:15][O:14][C:11]1[CH:10]=[C:6]2[C:5]([CH2:4][C:1](=[O:2])[O:8][C:7]2=[O:9])=[CH:13][CH:12]=1Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
To a suspension of 2-(carboxymethyl)-5-methoxybenzoic acid (5.22 g) (synthesised using the procedure in Tetrahedron 1975, 31, 2607-19) in acetone (50 ml) was added acetyl chloride (7.06 ml) and the reaction mixture was stirred at room temperature for 18 hours. The solvent was evaporated and azeotroped with toluene (×3). The resultant solid was triturated with diethyl ether to yield 7-methoxy-1H-isochromene-1,3(4H)-dione as a brown solid (4.36 g); NMR Spectrum: (DMSOd6) 3.84 (s, 3H), 4.20 (s, 2H), 7.36 (m, 2H), 7.50 (s, 1H).