Hydrochloric Acid → HCID 18679819, Verbindung

Reaktionsgleichung

[C:1]([C:5]1[CH:6]=[C:7]([CH2:12][CH2:13][C:14]([OH:16])=[O:15])[CH:8]=[CH:9][C:10]=1[OH:11])([CH3:4])([CH3:3])[CH3:2].[CH:17]([CH:19]=O)=[O:18].Cl>C(O)(=O)C>[C:1]([C:5]1[C:10]2[O:11][C:17](=[O:18])[CH2:19][C:9]=2[CH:8]=[C:7]([CH2:12][CH2:13][C:14]([OH:16])=[O:15])[CH:6]=1)([CH3:4])([CH3:2])[CH3:3]

Komponenten

Versuchsvorschrift

66.7 g (0.3 mol) of 3-(3-tert-butyl-4-hydroxy-phenyl)-propionic acid (prepared analogously to the method described in JP-A2-63/227542) in 58 g (0.4 mol) of aqueous glyoxal solution (40% by weight) and 3 ml of hydrochloric acid (32% by weight) are heated at reflux in 200 ml of acetic acid for 6 hours. The mixture is then poured into 600 ml of ice-water and the precipitate is filtered off. The filter residue is washed with water and then dried at 60° C. g. Recrystallisation from toluene results in 54.3 g (69% of theory) of 3-(7-tert-butyl-2-oxo-2,3-dihydro-benzofuran-5-yl)-propionic acid. Melting point 167-169° C.