A diaryl carbonate with a high degree of purity is produced at a high yield by (A) subjecting (a) a diaryl oxalate and a phenol compound or (b) an alkylaryl oxalate to transesterification reaction in one or two stages in the presence of a catalyst to prepare a diaryl oxalate, while removing a by-product from the reaction system; (B) collecting the diaryl oxalate from the resultant reaction product mixture of the step (A); (C) subjecting the diaryl oxalate to a decarbonylation reaction, preferably in the presence of a phosphorous compound-containing catalyst, to convert the diaryl oxalate to a corresponding diaryl carbonate, while removing a reaction by-product comprising carbon monoxide from the reaction system; and (D) collecting the diaryl carbonate from the reaction product mixture of the step (C).
PROCESS FOR PREPARING DIARYL ESTERS OF OXALIC ACID
申请人:UBE INDUSTRIES, LTD.
公开号:EP0814074A1
公开(公告)日:1997-12-29
The present invention relates to a process for producing a diaryl oxalate, characterized in that an alkylaryl oxalate is subjected to a disproportionation reaction in the presence of a disproportionation catalyst, thereby to produce a diaryl oxalate while removing a by-product comprising a dialkyl oxalate.
The production process of the present invention is advantageous in that the kinds of the by-products are fewer than that in conventional production process for diaryl oxalate, and thus can be practically utilized in industry, and the diaryl oxalates such as diphenyl oxalate, produced by the production process of the present invention are very important industrial materials for producing chemical products such as carbamates.