Catalytic action of calcium acetate and the manganese acetate–sodium acetate mixture in the pre‐esterification of dimethyl terephthalate with ethylene glycol

Products of pre‐esterification of dimethyl terephthalate with ethylene glycol at various times carried out with two catalysts, i.e., calcium acetate and a mixture of manganese and sodium acetates, were studied. Thin‐layer chromatography was used to follow the fundamental reaction and determine the type and degree of oligomerization. It was established that the manganese–sodium acetate mixed catalyst is more efficient both with regard to pre‐esterification and oligomerization.