One-dimensional architectures built from adamantane-bearing macrocycles with multiple propargyl groups

Abstract

Two macrocycles having adamantane, aromatic units, and propargyl groups (1, 2) were synthesized and their molecular alignments were investigated for the purpose of creating tubular and pseudopolyrotaxane structures. Macrocycles 1 and 2 have distinct molecular sizes and shapes and possess eight and four substituents, respectively. Each macrocycle afforded two inclusion crystals from two solvent systems. The two crystals of 1 had different macrocyclic backbones and orientation of propargyl groups, and columnar or tubular structures were constructed from 1. In the two crystals of 2, the macrocyclic skeleton and the propargyl groups adopted different geometries. In one crystal of 2, two of the substituents were mutually included within the cavity of the adjacent macrocycles to afford one-dimensional polymers with pseudorotaxane-like structures. In the other crystal of 2, the macrocycles were aligned to form columnar structures. Propargyl groups interacted with other units through mainly CH···π interactions.