A Supramolecular Artificial Light‐Harvesting System with Two‐Step Sequential Energy Transfer for Photochemical Catalysis

Abstract

An artificial light‐harvesting system with sequential energy‐transfer process was fabricated based on a supramolecular strategy. Self‐assembled from the host–guest complex formed by water‐soluble pillar[5]arene (WP5), a bola‐type tetraphenylethylene‐functionalized dialkyl ammonium derivative (TPEDA), and two fluorescent dyes, Eosin Y (ESY) and Nile Red (NiR), the supramolecular vesicles achieve efficient energy transfer from the AIE guest TPEDA to ESY. ESY can function as a relay to further transfer the energy to the second acceptor NiR and realize a two‐step sequential energy‐transfer process with good efficiency. By tuning the donor/acceptor ratio, bright white light emission can be successfully achieved with a CIE coordinate of (0.33, 0.33). To better mimic natural photosynthesis and make full use of the harvested energy, the WP5⊃TPEDA‐ESY‐NiR system can be utilized as a nanoreactor: photocatalyzed dehalogenation of α‐bromoacetophenone was realized with 96 % yield in aqueous medium.

Self-assembled metallasupramolecular cages towards light harvesting systems for oxidative cyclization

“… 2 In recent years, much attention has been focused by synthetic and material chemists to construct artificial LHSs via the FRET process which include conjugated polymers, porphyrin arrays, porous materials, dendrimers, and host–guest assemblies. 3 Among them supramolecular systems based on non-covalent interactions draw considerable attention in the synthesis of efficient FRET systems as they avoid a multistep synthetic process which is obligatory in the synthesis of scaffold covalent compounds. 4 Although some successful approaches were adopted for an efficient FRET process in supramolecular architectures based on covalent organic frameworks (COFs) 5 and metal organic frameworks (MOFs), 6 such systems are easy to synthesize but their poor solubility and stability in common solvents restrict their processability for further application.…”

Role of Functionalized Pillararene Architectures in Supramolecular Catalysis

“…The 4 @TPEDA‐ESY‐NiR‐based nanoreactor was successfully applied for the photocatalytic dehalogenation of α‐bromoacetophenone in an aqueous medium (Figure 11). [40] Compared to the reactions with ESY+NiR fluorescent dyes (31 %) as well as a blank and TPEDA control, the photocatalytic performance of the nanoreactor was significantly improved, with an optimized yield of 96 %. This was attributed to two factors: first, the loading of the fluorescent dyes into the hydrophobic, self‐assembled vesicles minimize photobleaching, and second, aggregation‐induced emission of the donor and fluorescent dyes arranged within the confined space avoid fluorescent quenching.…”

Organic supramolecular aggregates based on water‐soluble cyclodextrins and calixarenes

“…Other impressive applications of ALHSs in aqueous environments have been reported. For example, Tang and coworkers reported that a conjugated polymeric supramolecular network based on AIEgen displays an ultrahigh antenna effect, [ 92a ] Wang and coworkers reported a supramolecular ALHS for photochemical catalysis, [ 98 ] and Diao and coworkers reported stimulus‐responsive light‐harvesting complexes with photocatalytic activity. [ 99 ] In terms of optical behavior regulation, the assemblies formed by CDs and CAs are evenly matched.…”