Squaramide-Based Heteroditopic [2]Rotaxanes for Sodium Halide Ion-Pair Recognition.

ABSTRACT: A series of squaramide-based heteroditopic [2]rotaxanes consisting of isophthalamide macrocycle and squaramide axle components are synthesized using an alkali metal cation template-directed stoppering methodology. This work highlights the unprecedented sodium cation template coordination of the Lewis basic squaramide carbonyls for interlocked structure synthesis. Extensive quantitative ¹ H NMR spectroscopic anion and ion-pair recognition studies reveal the [2]rotaxane hosts are capable of cooperative sodium halide ion-pair mechanical bond axle-macrocycle component recognition, eliciting up to 20-fold enhancements in binding strengths for bromide and iodide, wherein the Lewis basic carbonyls and Lewis acidic NH hydrogen bond donors of the squaramide axle motif operate as cation a

SUBMITTER: Arun A 

PROVIDER: S-EPMC10946609 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature