Density functional theory study of benzoic acid decarboxylation

Mechanism of decarboxylation reaction includes, metal catalyst with Ag+, a radical path and oxidative decarboxylation have been investigated. The calculations have been done in two different B3LYP/LANL2DZ, and WB97XD/DGDZVP/ DEF2DTZV levels. Four structures have been proposed for oxidized benzoic acid. Among four possible oxidative structures only one structure with 62.99 kcal.mol-1 activation energy could lead to the decarboxylative product. Silver catalyzed decarboxylation leads to products in one step. The activation energy for this path have been determined to be 43.31 kcal.mol­-1. The radical path for decarboxylation needs 16.93 kcal.mol-1 although for radical creation it needs at least 100.12 kcal.mol-1 energy.