Gallic Acid → Exifone

Participants

Reaction Steps

A reaction of the Fries type was used: ##STR4## 32 g of Gallic acid, 32 g of pyrogallol, 55 g of anhydrous zinc chloride and 100 cm3 of phosphorus oxychloride were mixed in a balloon flask equipped with a condenser and an ampoule of calcium chloride, and were heated to 80° C for 2 hours. After cooling the reaction mixture, a mixture of water and ice was added, whereupon the reaction product precipitated. The reaction product was washed once with water, treated with a solution of sodium bicarbonate, then washed again with water, and finally recrystallised from aqueous solution. Yield: 15 g of crystalline 2,3,3',4,4',5'-hexahydroxybenzophenone having a melting point of 270° C.

Provenance & Evidence