Synthesis of 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane Dinitrate Hydrate and Its Disordered Crystal Structure

Abstract

4,7,13,16,21,24-Hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane dinitrate hydrate [H₂(Crypt-222)]²⁺⋅2NO ⁻₃ ⋅H₂O is prepared as a crystalline salt and studied by single crystal X-ray diffraction. In its crystal structure the 2,2,2-cryptand dication is disordered and has two different conformations with 55.3 and 44.7% probabilities. Hydrogen atoms of this dication at the two protonated bridgehead nitrogen atoms are directed inside the cavity. One of two NO ⁻₃ anions is also disordered and has two different orientations with 77 and 23% probabilities. Geometric parameters of the molecular ions and water molecule (bond lengths, bond angles, etc.) are determined with a reasonable accuracy, and their packing in the crystal structure is established.