VERFAHREN ZUR RUECKGEWINNUNG VON PYRIDIN ODER METHYLPYRIDINEN ODER DEREN GEMISCHE AUS BUTANDICARBONSAEUREMETHYLESTER ENTHALTENDEN REAKTIONSGEMISCHEN.

摘要

Prodn. of butanedicarboxylic acid methyl esters (I) is effected by reacting a methyl pentenoate (II) with CO and MeOH in the presence of pyridine and/or picolines (III) and a Co catalyst at elevated temp. and pressure, and treating the reaction mixt. with an O2-contg. gas and aq. HOAc. (III) are recovered by (a) sepg. the reaction mixt. into an aq. phase contg. Co(OAc)2, (III), HOAc and MeOH, and an organic phase contg. (I), by-products, (II), HOAc and (III); (b) extracting (III) from the organic phase with aq. HOAc; (c) combining the extract with the aq. phase; and (d) distilling (III) from the mixt. to leave an aq. soln. contg. Co(OAc)2 and HOAc.