Patent ID: 7435842
Filing Date: 2008-10-14
Classification: C07C

Abstract:
1. A method for producing a symmetrical carbonic ester, comprising: (1) performing a reaction between an organometal compound having a metal-oxygen-carbon linkage and carbon dioxide to obtain a reaction mixture containing a carbonic ester formed by the reaction, (2) separating said carbonic ester from said reaction mixture to obtain a residual liquid, and (3) reacting said residual liquid with a first alcohol to form at least one organometal compound having a metal-oxygen-carbon linkage and form water and removing said water from said at least one organometal compound, wherein said at least one organometal compound obtained in step (3) is recovered for recycle thereof to step (1), wherein said organometal compound used in step (1) comprises at least one compound selected from the group consisting of: an organometal compound represented by the formula (1): wherein: M each of R each of R each of a and b is an integer of from 0 to 2, a+b=0 to 2 each of c and d is an integer of from 0 to 4, and a+b+c+d=4; and an organometal compound represented by the formula (2): wherein: each of M each of R each of R e+f=0 to 2, g+h=0 to 2, each of i and j is independently an integer of from 1 to 3, e+f+i=3 and g+h+j=3, wherein R wherein said first alcohol used in step (3) has an organic group which is the same as the alkoxy group of the organometal compound used in step (1).