Borane catalyzed polymerization and depolymerization reactions controlled by Lewis acidic strength

Triphenylborane catalyzes the polymerization of anhydrides and epoxides along with the block co-polymerization of anhydride/epoxides with epoxides/CO2. Switching to the more Lewis acidic borane, tris(pentafluorophenyl)borane, the carbonate block of the polymer could be selectively depolymerized to yield the corresponding cyclic carbonate opening the door towards chemical repurposing of the polymer.

Automated summary

Triphenylborane catalyzes the polymerization of anhydrides and epoxides, while tris(pentafluorophenyl)borane can selectively depolymerize the carbonate block of the polymer to yield cyclic carbonates, allowing for chemical repurposing of the polymer.