PURPOSE: To obtain the subject compound useful as a raw material for polycarbonate, etc., in a short time in high yield by reacting a bisphenol with a dialkyl carbonate in the presence of an transesterifying catalyst under specific reaction condition.
CONSTITUTION: The objective bisalkylcarbonic acid ester (e.g. bismethylcarbonic acid ester) useful as a raw material for polycarbonate, etc., is produced in a short time in high yield by charging 1mol of a bisphenol (e.g. bisphenol A) and 100-400mol of a dialkyl carbonate (e.g. dimethyl carbonate) into an autoclave made of stainless steel, introducing 0.2-10mol of an transesterifying catalyst (e.g. dibutyltin oxide) into the autoclave, heating the content at 160°C in a stream of nitrogen gas and reacting the components while supplying the dialkyl carbonate to replenish the alcohol and dialkyl carbonate distilled out in the course of the reaction.
Shoichi Seo
Tsuyoshi Suzuki
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