Crystal structure of 3,14-dimethyl-2,13-di-aza-6,17-diazo-niatri-cyclo-[16.4.0.07,12]docosane bis-(per-chlorate) from synchrotron X-ray data

Acta Crystallogr E Crystallogr Commun. 2021 Apr 23;77(Pt 5):551-554. doi: 10.1107/S2056989021004278. eCollection 2021 May 1.

Abstract

The crystal structure of the title salt, C20H42N4 2+·2ClO4 -, has been determined using synchrotron radiation at 220 (2) K. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms. The asymmetric unit comprises one half of the organic dication, which lies about a center of inversion, and one perchlorate anion. The macrocyclic dication adopts the most stable endodentate trans-III conformation. The crystal structure is stabilized by intra-molecular N-H⋯N, and inter-molecular N-H⋯O and C-H⋯O hydrogen bonds involving the macrocycle N-H and C-H groups as donors and the O atoms of perchlorate anions as acceptors, giving rise to a three-dimensional network.

Keywords: crystal structure; hydrogen bonding; perchlorate; protonated macrocycle; synchrotron radiation.