Synthesis, Structure, and Properties of Supramolecular Charge-Transfer Complexes between Bis(18-crown-6)stilbene and Ammonioalkyl Derivatives of 4,4′-Bipyridine and 2,7-Diazapyrene

4,4′-Bipyridine and 2,7-diazapyrene derivatives (A) having two ammonioalkyl N-substituents were synthesized. The complex formation of these compounds with bis(18-crown-6)stilbene (D) was studied by spectrophotometry, cyclic voltammetry, 1H NMR spectroscopy, and X-ray diffraction analysis. In MeCN, π-donor D and π-acceptors A form supramolecular 1:1 (D·A) and 2:1 (D·A·D) charge-transfer complexes. The D·A complexes have a pseudocyclic structure as a result of ditopic binding of the ammonium groups to the crown-ether fragments. The better the geometric matching between the components, the higher the stability of the D·A complexes (log K up to 9.39). A key driving force of the D·A·D complex formation is the excessive steric strain in the precursor D·A complexes. The pseudocyclic D·A complexes involving the ammoniopropyl derivative of 4,4′-bipyridine were obtained as single crystals. Crystallization of the related ammonioethyl derivative was accompanied by transition of the D·A complexes to a structure of the (D·A)m coordination polymer type.