5-Hydroxymethylfurfural-Derived Boron-Dipyrromethene Immobilized on Resin Support as a Sustainable Catalyst for C-H Arylation of Heterocycles

Abstract

5-Hydroxymethylfurfural (HMF) was used as a sustainable raw material in the development of a resin-supported boron-dipyrromethene (BODIPY)-based photocatalyst. In the development of the catalyst, the brominated product (HMF-BODIPY-Br) and photocatalyst (HMF-BODIPY-Br-Suc) were isolated under a chromatography-free condition. The photocatalyst was loaded on polymeric resin by bridging alcohol functionality in HMF and amine functionality in polymeric resin using succinic anhydride. The resin-supported photocatalyst was used in light-mediated C-H arylation of various heterocycles using aryldiazonium salt. For representative examples, diazotization and photoarylation were carried out in one pot, and arylated furans were obtained in very good yields. C-H arylation was found to proceed via a photogenerated radical intermediate, and the radical intermediate was trapped by forming an adduct with TEMPO.