Responsive supramolecular gels were constructed from crown ether terminated four-arm star poly(epsilon-caprolactone) (PCL-DB24C8) and dibenzylammonium-terminated two-arm PCL-DBAS (see scheme), exploiting the formation of pseudorotaxane linkages between crown ether and ammonium moieties. The resultant supramolecular gels exhibit thermo- and pH-induced reversible gel-sol transition.

The creation of novel crown ether-paraquat polypseudorotaxane networks, constructed by bisparaquat monomers threading into the cavity of the crown ether units of linear supramolecular polymers that are formed based on the quadruple hydrogen bonded unit ureidopyrimidinone (Upy) in the concentrated solution, is described.

Photochemistry, Fluorescence, Crown Ethers, Biology The complexing of thallous ions (T1+), with the crown ether dibenzo 18 crown-6 polyether (DB) has been studied by NMR, fluorescence, and pulse radiolysis techniques. NMR data show a strong interaction of the T1+ ions with the aromatic moieties. This is also illustrated by a static quenching of the aromatic fluorescence by Tl+. The rates of rea...

In the title compound, C(6)H(7)ClN(+)·ClO(4) (-)·C(12)H(24)O(6), the cation forms a 1:1 complex with the crown ether, viz [C(6)H(7)ClN-(18-crown-6)](+), in which the -NH(3) (+) unit nests in the crown and inter-acts with it through bifurcated N-H⋯O hydrogen bonding. All constituents of the structure have crystallographically imposed mirror symmetry except for the H atoms of the -NH(3) (+) group...

The conformation of benzo-18-crown-6-ether (B18C6) and its water encapsulation in a supersonic beam are investigated by laser-induced fluorescence (LIF), UV-UV hole-burning, IR-UV double-resonance (IR-UV DR), and resonance-enhanced multiphoton ionization (REMPI) spectroscopy with the aid of density functional theory (DFT) calculations at the B3LYP/6-31+G* level. At least four B18C6 conformers a...

The conformation of benzo-18-crown-6-ether (B18C6) and its encapsulation of water molecules in a supersonic beam are investigated by laser induced fluorescence (LIF), UV-UV hole-burning, IR-UV double resonance (IR-UV DR), and resonance-enhanced multiphoton ionization (REMPI) spectroscopy with the aid of density functional theory (DFT) calculations at the B3LYP/6-31+G* level. At least four B18C6...

A crown ether-functionalized poly(tetraphenylethene) (AP-TPE) is synthesized and the rotation of the TPE group is successfully restricted via the complexation of crown ether and organic ammonium salts, leading to a stepwise enhanced fluorescence accompanied by a morphological transition from micellar to vesicular.

A bolaamphiphilic low-molecular-weight gelator based on crown ether, which could self-assemble into organogels and hydrogels, was prepared. The contribution of each part of the structure to the gelation property was investigated by designing a series of analogues. A simple framework (crown ether-hydrophobic linkage-ammonium salt) was proposed.

In addition to the ammonium-crown ether recognition, pi-stacking interactions between the C60 sphere and the porphyrin moiety have been evidenced in a supramolecular complex obtained from a porphyrin-crown ether conjugate and a fullerene derivative bearing an ammonium unit.

A new crown ether-POM (POM = polyoxometalate) adduct with the molecular formula [(C14H20O5)4(H3O)3]PMo12O40 · 0.5CH3CN (1) was isolated from the mixed solvent of acetonitrile and methanol. The adduct is constructed from Keggin [PMo12O40]3− anions and [(C14H20O5)(H3O)] and [(C14H20O5)2(H3O)] cations via electrostatic and hydrogen bonding interactions. The supramolecular interactions combine the ...