Synthesis and Crystal Structure of 1,10-Diazonia-18-crown-6 Diiodide Dihydrate

Abstract

Crystalline 1,10-diazonia-18-crown-6 diiodide dihydrate was synthesized and studied by single crystal X-ray diffraction. The salt exists in the crystal in the form of separate centrosymmetrical ionic molecules [(H2DA18C6)2+ ⋅ 2I− ⋅ 2H2O] whose components are held together by hydrogen bonds and electrostatic attraction forces. The centrosymmetric dication DA18C6 (with two protonated nitrogen atoms) has a crown conformation with approximate D3d symmetry. The iodide ions are arranged at the nitrogen atoms (one above and the other below) of the DA18C6 dication, and two water molecules are arranged above and below its symmetry center. Each water molecule is disordered over two positions with occupancies of 0.65 and 0.35.