Transesterification of methyl benzoate and dimethyl terephthalate with ethylene glycol over superbases

The catalytic behavior of the superbases Na/NaOH/gamma-Al2O3 and CsxO/gamma -Al2O3 was investigated in the transesterification of methyl benzoate and d imethyl terephthalate with ethylene glycol. The reactions were carried out in liquid phase under atmospheric pressure. The dependencies of conversion, selectivity and product distribution on temperature, reactant/catalyst rat io and the starting material ratio were investigated. In the transesterific ation of methyl benzoate selectivites to ethylene glycol monobenzoate up to 96% at conversions up to 94% have been observed. In the transesterificatio n of dimethyl terephthalate yield of bis(2-hydroxyethyl) terephthalate of 8 8% is obtained. (C) 1999 Elsevier Science B.V. All rights reserved.