Photocatalytic Direct Decarboxylation of Carboxylic Acids to Derivatize or Degrade Polymers

Angew Chem Int Ed Engl. 2022 Oct 4;61(40):e202209085. doi: 10.1002/anie.202209085. Epub 2022 Sep 5.

Abstract

Visible light-mediated direct decarboxylation of carboxylic acids with an acridine photocatalyst is a convenient and powerful method to generate carbon-centered radicals in polymer chains. Advantageously, this process proceeds under mild conditions, without preactivation of the acid groups. We utilize decarboxylation in the presence of a hydrogen atom donor to form statistical acrylate-ethylene and acrylate-propylene copolymers, which are challenging to obtain by direct polymerization. We additionally show that decarboxylation of methacrylic acid units within polymethacrylates can trigger degradation of the polymer backbones. Moreover, a dual catalytic approach, which combines the function of an acridine photocatalyst with that of a cobaloxime catalyst, is leveraged to furnish unique copolymers with pendent alkenes. Our work indicates that direct decarboxylation is a versatile technique for the synthesis of functional materials with tailored compositions and properties.

Keywords: Acridine; Decarboxylation; Degradation; Photocatalysis; Polymers.