Acetic Acid → Benzoic acid, 4-(acetyloxy)-

Participants

Reaction Conditions

Reaction Steps

One hundred and sixty-six (166) g (0.933 mole) of p-acetoxyacetophenone, 100 g (0.98 mole) of acetic anhydride, 250 g (4.17 moles) of acetic acid, 0.35 g (0.0014 mole) of Co(OAc)2.4H2O, 0.35 g (0.0014 mole) of Mn(OAc)2.4H2O, and 0.47 g (0.0028 mole) of 48% HBr were combined in a two-liter titanium-clad autoclave. The mixture was heated to 300° F. and pressurized to 300 psi. Air was introduced at a rate of 0.75 scf/min for 15 minutes and then lowered to 0.61 scf/min for the remainder of the reaction. During the run, a solution of 150 g (1.47 moles) of acetic anhydride and 38 g (0.63 mole) of acetic acid was added through a pump. The run time was 31 minutes. The reaction solution was concentrated by evaporating acetic acid from 696 g to 660 g. The precipitated p-acetoxybenzoic acid was isolated by filtration and dried to give 81.3 g of 97.6 mole % purity (47.2 mole % yield). Analysis of the filtrate showed: p-acetoxybenzoic acid, 32 mole %, p-hydroxybenzoic acid, 0.3 mole %, and p-acetoxyacetophenone, 3.2 mole %. Analysis of the reactor wash showed p-acetoxyacetophenone, 2.1 mole %. Total reaction yield of p-acetoxybenzoic acid was 81.3 mole %.

Provenance & Evidence