Extremely strong tubular stacking of aromatic oligoamide macrocycles

Authors

Mark A. Kline, State University of New York at Buffalo
Xiaoxi Wei, State University of New York at Buffalo
Ian J. Horner, State University of New York at Buffalo
Rui Liu, State University of New York at Buffalo
Shuang Chen, University of Nebraska-Lincoln
Si Chen, Argonne National LaboratoryFollow
Ka Yi Yung, State University of New York at Buffalo
Kazuhiro Yamato, State University of New York at Buffalo
Zhonghou Cai, Argonne National LaboratoryFollow
Frank V. Bright, State University of New York at BuffaloFollow
Xiao Cheng Zeng, University of Nebraska-LincolnFollow
Bing Gong, State University of New York at BuffaloFollow

Date of this Version

2015

Citation

Chemical Science, 2015, 6, 152. DOI: 10.1039/c4sc02380c

Comments

© The Royal Society of Chemistry 2015. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.

Abstract

As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of K_dimer > 10¹³ M^–1 in CHCl₃), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (–49.77 kcal mol^–1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results in well-aligned tubular stacks. The persistent tubular assemblies of 3, with their non-deformable sub-nm pore, are expected to possess many interesting functions. One such function, transmembrane ion transport, is observed for 3.

Includes supplemental material.