Tetraphenylethylene-based photoresponsive supramolecular organic framework and its metallization for photocatalytic redox reactions

Abstract

Fabrication of effective photocatalysts for efficient reactions under mild conditions and light irradiation is significantly important but challenging. Herein, considering both photoresponsive tetra-methoxynaphthyl tetraphenylethylene (NA-TPE) and bi(methyl)viologen-based bipyridine (MV-DPY) molecules as key organic modules, a supramolecular organic framework (SOF) MVDPY-NATPE-CB[8] was assembled in the presence of cucurbit[8]uril (CB[8]) via encapsulation-enhanced donor–acceptor interaction for photocatalytic reactions. Catalytic studies revealed that the assembled MVDPY-NATPE-CB[8] framework can trigger the generation of reactive oxygen species (ROS), including singlet oxygen (¹O₂) and superoxide anion radicals (O₂˙⁻), for the photocatalytic aerobic oxidation of N-phenyltetrahydroisoquinoline and hydroazobenzene. Moreover, after being coordinated with nickel ions, nickel metallized MVDPY-NATPE-CB[8] (Ni-MVDPY-NATPE-CB[8]) demonstrates a remarkable efficiency in the photocatalysis of the C–S cross-coupling reaction in an aqueous environment. This study demonstrates that rationally assembled photoresponsive SOF materials can be an effective platform for photocatalysis.