Therefore, it was concluded that this reaction, conducted in the solid phase in plant material with a high fraction of carboxylic acids, follows a pseudo first order kinetics in which a nearby carboxylic acid precipitates without affecting the observed rate constant. Two transition states corresponding to indirect and direct keto-enol routes are possible, with energies of 93 and 104 kJ/mol. Both intermediates involve protonation of the alpha carbon, disrupting one of the double bonds of the aromatic ring and permitting the beta-keto group (which takes the form of an enol in THCA and THC) to participate in decarboxylation. In beverages stored for long periods, very small amounts of benzene may form from benzoic acid by decarboxylation catalyzed by the presence of ascorbic acid. The addition of catalytic amounts of cyclohexenone has been reported to catalyze the decarboxylation of amino acids. However, using such catalysts may also yield an amount of unwanted by-products.