Patent ID: 9156803
Filing Date: 2015-10-13
Classification: B01J,C07D,Y02P

Abstract:
1. A method of synthesizing an acid anhydride comprising the steps of: a) feeding a reaction stream comprising an epoxide, at least one catalyst, at least one solvent, and carbon monoxide to a reaction vessel under reaction conditions to promote a double carbonylation of the epoxide to form dissolved acid anhydride in the reaction vessel, which exits the reaction vessel in a reaction product stream in a continuous flow process; b) treating the reaction product stream containing dissolved acid anhydride to conditions that cause the acid anhydride to crystallize such that the reaction product stream comprises crystallized acid anhydride and a liquid phase comprising dissolved catalyst and solvent; c) separating the crystallized acid anhydride from the liquid phase; and d) recycling the liquid phase comprising dissolved catalyst and solvent to the reaction stream comprising the epoxide; wherein the catalyst comprises a transition metal carbonyl compound and further comprises a Lewis acidic co-catalyst.