Malonic Acid → 3-Allyl-4-hydroxy-cinnamic acid

Reaction equation

C(O[C:5]1[CH:6]=[C:7]([CH:10]=[CH:11][C:12]=1[OH:13])[CH:8]=O)C=C.[C:14]([OH:20])(=[O:19])[CH2:15]C(O)=O.N1CC[CH2:24][CH2:23][CH2:22]1>N1C=CC=CC=1>[CH2:24]([C:5]1[CH:6]=[C:7]([CH:10]=[CH:11][C:12]=1[OH:13])[CH:8]=[CH:15][C:14]([OH:20])=[O:19])[CH:23]=[CH2:22]

Participants

Procedure

48.5 g (0.27 mol) of 3-allyloxy-4-hydroxy-benzaldehyde, 104 g (1 mol) of malonic acid, 140 ml of pyridine and 4 ml of piperidine are heated to 100° C. for 2 hours, whilst stirring. The volatile constituents are distilled off under reduced pressure at 80° C. and the residue is stirred with 800 ml of water. The crystals obtained are filtered off and recrystallised from methylene chloride. 3-Allyl-4hydroxy-cinnamic acid of melting point 132°-133° C. is obtained.