公开(公告)号：US11661416B2

公开(公告)日：2023-05-30

申请号：US17049601

申请日：2019-05-13

Applicant: SABIC GLOBAL TECHNOLOGIES B.V.

Inventor： Aaron Matthew Royer ,  Sivakumar Periyasamy ,  Ravi Gautam ,  Jorge Jimenez Umana ,  Gregory L. Hemmer ,  Robert Werling ,  Hareesh Shamrao Deshpande

IPC: C07D405/12 ,  C07D407/12

CPC classification number: C07D405/12 ,  C07D407/12

Abstract: A method for producing an aromatic dianhydride includes reacting an aromatic diimide with a substituted or unsubstituted phthalic anhydride in an aqueous medium in the presence of an amine exchange catalyst to provide an aqueous reaction mixture including an N-substituted phthalimide, an aromatic tetraacid salt, and at least one of an aromatic triacid salt and an aromatic imide diacid salt. The method further includes removing the phthalimide from the aqueous reaction mixture by extracting the aqueous reaction mixture with an organic solvent in a first extractor for a first time period, at a first extraction temperature and subsequent to the first time period, extracting the aqueous reaction mixture with an organic solvent in a second extractor for a second time period, at a second extraction temperature. The aromatic tetraacid salt is converted to the corresponding aromatic dianhydride. Aromatic dianhydrides prepared according to the method are also described.