Self-Assembled Perylene Bisimide-Cored Trigonal Prism as an Electron-Deficient Host for C₆₀ and C₇₀ Driven by “Like Dissolves Like”

Abstract

Poor processability of fullerenes is a major remaining drawback for them to be studied monomolecularly and to find real-life applications. One of the strategies to tackle this problem is to encapsulate them within a host, which is however quite often, accompanied by significant alteration of their physical/chemical properties as encountered in chemical modification. To minimize the effect, an electron-deficient entities-based, dissolvable, and fluorescence active supramolecular host was designed and constructed via coordination-driven self-assembly of o-tetrapyridyl perylene bisimide (PBI) with cis-(PEt3)2Pt­(OTf)2. The trigonal prism 1 possesses a trigonal-prismatic inner cavity with 14.7 Å as the diameter of its inscribed circle. Host–guest chemistry investigations revealed that both C60 and C70 could be quantitatively encapsulated by the host in a 1:1 ratio. Further studies demonstrated that the produced host–guest complex 1⊃C 70 is significantly more stable than 1⊃C 60 , allowing complete transformation of the latter to the former and separation of C70 from its mixture with C60. The fullerenes in the inclusion state could rotate freely within the cavity. Electrochemistry and spectroscopy studies disclosed that the encapsulation of the guests shows little effect upon the reduction of the host and its fluorescence properties. Thus, “like dissolves like” is believed to be the main driving force for the formation of the host–guest complexes. Moreover, the host and host–guest complexes can be fabricated into monomolecular membranes using the conventional Langmuir–Blodgett technique. We propose that these unique host–guest complexes could be used as model ensembles for further studies of the physical/chemical properties of fullerenes in both single molecular and 2D membrane states. In addition, their reversible four-electron reduction property may allow them to find applications in photo/electrocatalysis, organic electronics, etc.

Highly Emissive Perylene Diimide-Based Metallacages and Their Host–Guest Chemistry for Information Encryption

“…These values are among the highest binding constants for emissive metallacage-based host-guest interactions. [20][21][22][23][24][25][26][27][28][29][30][31][32] The binding affinity of metallacages towards PAHs is attributed to the π-π stacking interactions between the electrondeficient PDI and the electron-rich PAHs. Because of slightly different sizes and shapes of the three PAHs, it is likely that they will have different binding modes and energies with PDI-based metallacages, which gives them different binding affinities with the two metallacages.…”

Photo-assisted charge/discharge Li-organic battery with a charge-separated and redox-active C60@porous organic cage cathode

“…S11 and S12, ESI†), the proton signals of the aryl and enamine groups in C 60 @POC split and shift in comparison with that of POC, which can be ascribed to the possible π–π interaction between C 60 and POC. 23 To reveal the stoichiometry between POC and C 60 , electrospray ionization time of flight mass spectrometry (ESI-TOF-MS) was conducted. The ESI-TOF-MS spectrum of POC (Fig.…”

High-Performance NMHC Detection Enabled by a Perylene Bisimide-Cored Metallacycle Complex-Based Fluorescent Film Sensor

“…The stereoscopic structure of PBI-based SCCs shows different photophysical behaviors compared to the PBI and enhanced sensing performance by improving the mass transfer process and the intermolecular interaction via the formation of a molecular channel. 38 As a proof-of-principle, a new PBI-containing self-assembled metallacycle is prepared via the strategy of coordination-driven self-assembly. In brief, a PBI derivative containing pyridine groups (ligand 3, Scheme S1, Figures S1 and S2) is designed and synthesized, which is mixed with cis-(PEt 3 ) 2 Pt(OTf) 2 and potassium isophthalate to produce the PBI-containing metallacycle (Scheme 1).…”

“…Recently, incorporating fluorophores within supramolecular coordination complexes (SCCs) has been another effective approach to produce new high-performance fluorescent materials. − SCCs are constructed via the strategy of ligand-coordination self-assembly and have merits of moderate bonding energy, predictability, and high directionality. − For example, discrete structures and well-defined cavities endow the PBI-based SCCs with good solubility and processability. The stereoscopic structure of PBI-based SCCs shows different photophysical behaviors compared to the PBI and enhanced sensing performance by improving the mass transfer process and the intermolecular interaction via the formation of a molecular channel …”