Hydrochloric Acid → 10-(2-Hydroxy-3,4-dimethoxy-6-methylphenyl)decanoic acid

Reaction equation

[OH:1][C:2]1[C:20]([O:21][CH3:22])=[C:19]([O:23][CH3:24])[CH:18]=[C:17]([CH3:25])[C:3]=1[C:4]([CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][C:14]([OH:16])=[O:15])=O.C1(C)C=CC=CC=1.Cl>O>[OH:1][C:2]1[C:20]([O:21][CH3:22])=[C:19]([O:23][CH3:24])[CH:18]=[C:17]([CH3:25])[C:3]=1[CH2:4][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][C:14]([OH:16])=[O:15]

Participants

Procedure

9-(2'-Hydroxy-3',4'-dimethoxy-6'-methylbenzoyl)nonanoic acid (formula II-1, wherein R=H3CO, X=H, Y=OH, n=8, in the free form) (0.254 part), zinc amalgam (0.56 part), toluene (1 volume part), 35% hydrochloric acid (0.5 volume part) and a small proportion of water were refluxed for 5 hours. The toluene layer was separated and the water layer was extracted with diethyl ether. The toluene layer was combined with the ethereal layer, washed with water and dried. The solvents were then distilled off under reduced pressure and the residue was recrystallized from ligroine. The foregoing procedure provided 10-(2'-hydroxy-3',4'-dimethoxy-6'-methylphenyl)decanoic acid (formula II-2 wherein R=H3CO, X=H, n=8, in the free form) (0.14 part) as colorless powdery crystals melting at 62.5°-66° C.