A Highly Efficient\nSupramolecular Polymer-Based Singlet\nOxygen Generator for Photocatalytic Minisci Alkylation

Supramolecular polymers, with their specific functional\nunits and\nstructures, can effectively enhance the absorption and utilization\nof light energy, thereby facilitating more efficient photocatalytic\norganic reactions. In the present work, we constructed a supramolecular\npolymer consisting of benzothiazole derivatives (BTBP) and cucurbit[8]uril\n(CB[8]). The BTBP monomer, known for its unique chemical structure\nand properties, has been found to exhibit a remarkable capability\nin generating singlet oxygen (<sup>1</sup>O<sub>2</sub>). As a result\nof the constraining impact of the macrocyclic molecule, the inclusion\nof CB[8] resulted in an effective enhancement in the ability to generate <sup>1</sup>O<sub>2</sub> while forming supramolecular polymer BTBP–CB[8].\nWhen evaluating the quantum yield of <sup>1</sup>O<sub>2</sub> using\nRose Bengal (RB) as a reference photosensitizer (75% in water), BTBP–CB[8]\ndemonstrated an enhanced <sup>1</sup>O<sub>2</sub> quantum yield compared\nto BTBP, with an impressive yield of 152.4%, demonstrating that the\nformation of supramolecular polymer contributes to its ability to\ngenerate <sup>1</sup>O<sub>2</sub>. Subsequently, BTBP–CB[8],\na highly efficient <sup>1</sup>O<sub>2</sub> generator, was employed\nfor the photocatalytic Minisci alkylation reaction, resulting in an\nimpressive reaction yield of up to 89%. The supramolecular polymer\nstrategies employed in the construction of photocatalytic systems\nhave exhibited remarkable efficacy in the production of <sup>1</sup>O<sub>2</sub>, underscoring their immense prospects in photocatalysis.