Anion-directed assembly of a rectangular supramolecular cage in the solid state with electron-deficient phenoxylated oxacalix[2]arene[2]triazine.

Chloride-π interaction along with lone-pair electrons-π interaction, hydrogen bonding and π-π stacking induced the hexameric assembly of the parent macrocycle into a rectangular supramolecular cage in the solid state.

Highly efficient construction of large molecular cavity using 1,3-alternate tetraoxacalix[2]arene[2]triazine as a platform.

In the presence of K(2)CO(3) in refluxing THF, dichloro-substituted tetraoxacalix[2]arene[2]triazine, a readily available macrocyclic compound from cyanuric acid chloride and benzyl 1,3-dihydroxybenzoate, underwent highly efficient nucleophilic displacement reactions with bis-nucleophilic reagents of different geometry, length and chirality in a 2+2 fashion to produce large and size-tunable cavity bis-tetraoxacalix[2]arene[2]triazines in good to excellent yields.

Synthesis and structure of upper-rim 1,3-alternate tetraoxacalix[2]arene[2]triazine azacrowns and change of cavity in response to fluoride anion.

The upper-rim 1,3-alternate tetraoxacalix[2]arene[2]triazine azacrowns were constructed effectively by macrocyclic condensation reaction of diamines with dichlorinated tetraoxacalix[2]arene[2]triazine intermediates that were synthesized from the stepwise fragment coupling reactions of 3,5-dihydroxybenzoic acid esters with cyanuric chlorides. Because of the formation of conjugation of amino groups with triazine rings, tetraoxacalix[2]arene[2]triazine azacrowns existed in a mixture of syn- and anti-isomeric forms. Both fluorescence titration and 1H NMR spectroscopic study showed that tetraoxacalix[2]arene[2]triazine azacrowns interacted with fluoride anion, leading to cavity changes of the host molecules.