Water-soluble calix[4]arenes 10a,b with chromophores ("antenna") attached to the lower rim via a short spacer are described. In the neutral lanthanide complexes of 10a,b photoexcitation of the antenna induces lanthanide emission via intramolecular energy transfer. Calix[4]arene 10b with a chrysene moiety as sensitizer shows strong lanthanide emission for Eu(3+) with an excitation maximum at lam...

The open-close states of the ion channels in a living system are regulated by multiple stimuli such as ligand, pH, potential and light. Functionalizing natural channels by using synthetic chemistry would provide biological nanopores with novel properties and applications. Here we use para-sulfonato-calix[4]arene-based host-guest supramolecular system to develop artificial gating mechanisms aimi...

Calix[4]arene derivatives supported on monolayer protected gold clusters show a remarkable enhanced binding efficiency towards quaternary ammonium salts in homogeneous solution of apolar solvents with respect to the corresponding unsupported hosts.

the conformational behavior of monosubstituted tri-methylsilyle ethynyl derivative of cal ix[4]arene as a newgeneration of caliarene was compared with tetra alkylated calyx[4]arene. the most important conformationalphenomena in these compounds which are pinched cone interconversion process were done by semi-empiricalmethod and ab initio calculations with gaussian 98w programming.

the solvent extraction of rare earth metal ions from nitrate solutions by 5.11.17.23-tetra-tert-butyl-25,27-bis(diethylcarbamoylmethoxy)-26,28-dihydroxycalix[4]arene (l) in 1,2-dichloroethane has been investigated. the alalysis of the extraction equilibrium obtained from a mixture of la3+, eu3+, er3+ and y3+ revealed that the extracted species have a 1:1 metal/ligand ratio. the intra-group sepa...

The structures of three novel compounds prepared from the reaction of the lower-rim 1,3-diacid calix[4]arene (LH(2)) with lithium carbonate (1), t-butyl-lithium (2) and zinc acetate (3) are reported.

Inherently chiral biscalix[4]arenes have been designed and synthesized by covalently assembling two calix[4]arene building blocks in a 1,3-position linking with 1,2-position pattern at the lower rims via two triethylene glycol bridges.

The calix[4]arene niobium(III) complex ([L]Nb-N=N-Nb[L] where [L] = p-tert-butylcalix[4]arene), reported to bind N(2) in a μ(2)-linear dimeric capacity and to activate the N(2) triple bond to 1.39 Å, corresponding to the longest N(2) bond known in the end-on coordination mode, was subjected to a computational investigation involving both density functional and wavefunction based methods to esta...