1-(2,3,4-Trihydroxyphenyl)propan-1-one

synthetischePreparation by acylation of pyrogallol with propionic acidin the presence of boron trifluoride in ethyl ether for 1 h at 0° (80%) in the presence of Amberlite IR-120 (cation exchange resin sulfonic acid type) at 160° for 2–3 h (78%) Zeokarb 225 was found to be as effectivein the presence of zinc chloride, at 130–140° for 90 min (Nencki reaction) (35%) in the presence of 70% perchloric acid at reflux for 1 h (33%) Preparation by reaction of propionyl chloride with pyrogallol and heating 4 h on a water bath (75%) Preparation by acylation of pyrogallol with propionic anhydridein the presence of Amberlite IR-120 (cation exchange resin sulfonic acid type) at 160° for 2–3 h (79%) Zeokarb 225 was found to be as effectivein the presence of concentrated sulfuric acid (small drops) at 130° for some min (65%) in the presence of zinc chloride, but using a mixture of propionic acid/propionic anhydride (85/100) at 135–140° for 40 min, then at r.t. overnight (59%).