Rose Bengal Immobilized on Wool as an Efficiently “Green” Sensitizer for Photooxygenation Reactions

Abstract A new type of supported photosensitizer derived from renewable wool and Rose Bengal is described. The novel sensitizer could efficiently promote the photooxygenation of furan derivatives to the corresponding 5-hydroxy-2-(5H)-furanone in excellent yields, via singlet oxygen, using visible light as the energy source. The sensitizer could be easily recovered from the reaction mixture by a simple filtration. It is discovered that the recovered sensitizer can be reused four times.