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CH···O hydrogen bonds in "clicked" diketopiperazine-based amide rotaxanes. | LitMetric

Two amide [2]rotaxanes were synthesized in high yields using a novel N,N'-dipropargyl diketopiperazine axle centerpiece as the template to which the stoppers are attached through "click chemistry". (1)H and 2D NMR spectra provide evidence for two different H-bonding motifs, in one of which the triazole CH groups form C-H···O═C bonds with the wheel carbonyl O atoms. This motif can be controlled and switched reversibly by competitive anion binding.

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http://dx.doi.org/10.1021/ol201915jDOI Listing

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