Supramolecular Side-Chain Poly[2]pseudorotaxanes Formed by Orthogonal Coordination-Driven Self-Assembly and Crown-Ether-Based Host–Guest Interactions

The themes of coordination-driven self-assembly, host–guest interactions, and supramolecular polymerization are unified in an orthogonal noninterfering fashion to deliver side-chain poly[2]­pseudorotaxanes. Specifically, a bis­(<i>p</i>-phenylene)-34-crown-10 derivative <b>1</b> bearing two pyridyl groups polymerizes into a side-chain poly[2]­pseudorotaxane upon the addition of di-Pt­(II) acceptor <b>4</b> in the presence of paraquat. Interestingly, by adding a competitive guest <b>3</b>, the poly[2]­pseudorotaxane can realize a conversion in one pot

Supramolecular Side-Chain Poly[2]pseudorotaxanes Formed by Orthogonal Coordination-Driven Self-Assembly and Crown-Ether-Based Host–Guest Interactions

The themes of coordination-driven self-assembly, host–guest interactions, and supramolecular polymerization are unified in an orthogonal noninterfering fashion to deliver side-chain poly[2]­pseudorotaxanes. Specifically, a bis­(<i>p</i>-phenylene)-34-crown-10 derivative <b>1</b> bearing two pyridyl groups polymerizes into a side-chain poly[2]­pseudorotaxane upon the addition of di-Pt­(II) acceptor <b>4</b> in the presence of paraquat. Interestingly, by adding a competitive guest <b>3</b>, the poly[2]­pseudorotaxane can realize a conversion in one pot

Metallosupramolecular Poly[2]pseudorotaxane Constructed by Metal Coordination and Crown-Ether-Based Molecular Recognition

A novel bis­(<i>m</i>-phenylene)-32-crown-10 derivative bearing two π-extended pyridyl groups was synthesized, and its host–guest complexation with a paraquat derivative to form a threaded [2]­pseudorotaxane was studied. Subsequently, a poly[2]­pseudorotaxane was constructed with a metallosupramolecular polymer backbone via metal coordination, which was comprehensively confirmed by the combination of ¹H NMR, ³¹P­{¹H} NMR, DOSY NMR, DLS, and EDX techniques

Chemically-Responsive Complexation of A Diquaternary Salt with Bis(<i>m</i>‑phenylene)-32-Crown-10 Derivatives and Host Substituent Effect on Complexation Geometry

A chemically responsive diquaternary salt with π-extended surface was made. The host–guest complexation with chemo-responsiveness between three bis(<i>m</i>-phenylene)-32-crown-10 (BMP32C10) derivatives and this diquaternary salt guest was studied through the sequential addition of basic and acidic reagents (diethylamine and trifluoroacetic acid, respectively). Furthermore, the host-substituent effect on the complexation geometries of these three host–guest complexes, from taco to taco-type threaded to threaded structures by changing the substituent on BMP32C10 as shown by crystal structures, was also addressed

Chemically-Responsive Complexation of A Diquaternary Salt with Bis(<i>m</i>‑phenylene)-32-Crown-10 Derivatives and Host Substituent Effect on Complexation Geometry

A chemically responsive diquaternary salt with π-extended surface was made. The host–guest complexation with chemo-responsiveness between three bis(<i>m</i>-phenylene)-32-crown-10 (BMP32C10) derivatives and this diquaternary salt guest was studied through the sequential addition of basic and acidic reagents (diethylamine and trifluoroacetic acid, respectively). Furthermore, the host-substituent effect on the complexation geometries of these three host–guest complexes, from taco to taco-type threaded to threaded structures by changing the substituent on BMP32C10 as shown by crystal structures, was also addressed

Metallosupramolecular Poly[2]pseudorotaxane Constructed by Metal Coordination and Crown-Ether-Based Molecular Recognition

A novel bis­(<i>m</i>-phenylene)-32-crown-10 derivative bearing two π-extended pyridyl groups was synthesized, and its host–guest complexation with a paraquat derivative to form a threaded [2]­pseudorotaxane was studied. Subsequently, a poly[2]­pseudorotaxane was constructed with a metallosupramolecular polymer backbone via metal coordination, which was comprehensively confirmed by the combination of ¹H NMR, ³¹P­{¹H} NMR, DOSY NMR, DLS, and EDX techniques

Benzo-21-crown-7-Based [1]Rotaxanes: Syntheses, X‑ray Crystal Structures, and Dynamic Characteristics

Two B21C7-based [1]rotaxanes were synthesized in high yields by means of copper(II)-mediated Eglinton coupling and a subsequent Pd/C-catalyzed reduction under H₂. X-ray single-crystal analysis shows that [1]rotaxane takes on a self-entangled conformation, wherein the macrocycle is threaded by its own tail. Moreover, it was found that [1]rotaxane with a flexible skeleton had more rotational motions than that of one with a rigid skeleton

Benzo-21-Crown-7/Secondary Ammonium Salt [2]Rotaxanes with Fluoro/Chlorocarbon Blocking Groups

Three threaded structures capped by fluoro/chlorocarbon blocking groups with different sizes were constructed by template synthesis based on the benzo-21-crown-7/secondary ammonium salt recognition motif, as confirmed by ¹H NMR, electrospray mass spectrometry and single crystal X-ray analysis. The transformation from a rotaxane-like entity into a rotaxane was achieved by replacing the end group from the trifluoroacetic ester group to its trichloroacetic ester analogue

Three Protocols for the Formation of a [3]Pseudorotaxane <i>via</i> Orthogonal Cryptand-Based Host–Guest Recognition and Coordination-Driven Self-Assembly

A novel bis(<i>m</i>-phenylene)-32-crown-10-based cryptand <b>1</b> with a pyridine nitrogen atom outside on the third arm was designed and synthesized. Subsequently, host–guest complexation between cryptand <b>1</b> and a selection of bipyridinium guests has been studied. More interestingly, the [3]pseudorotaxane <b>2</b>⊃<b>5</b>₂ was obtained in three methods by utilizing the noninterfering orthogonal nature of coordination-driven self-assembly and host–guest interactions

A Supramolecular Cross-Linked Conjugated Polymer Network for Multiple Fluorescent Sensing

A supramolecular cross-linked network was fabricated and demonstrated to act as a multiple fluorescent sensor. It was constructed from a fluorescent conjugated polymer and a bisammonium salt cross-linker driven by dibenzo[24]­crown-8/secondary ammonium salt host–guest interactions. Compared with the conjugated polymer, the network has weak fluorescence due to the aggregation of polymer chains. Thanks to the multiple stimuli-responsiveness of host–guest interactions, the fluorescence intensity of the system can be enhanced by four types of signals, including potassium cation, chloride anion, pH increase, and heating. Hence, the network can serve as a cation sensor, an anion sensor, a pH sensor, and a temperature sensor. It can be used in both solution and thin film. Interestingly, exposure of a film made from this supramolecular cross-linked network to ammonia leads to an increase of fluorescence, making it a good candidate for gas detection