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Dynamic covalent reactions are widely used in dynamic combinatorial chemistry. Most of these reactions are run under differing reaction conditions and exhibit cross-reactivity when components of multiple reactions are present in one reaction vessel. Herein, we report the study of four dynamic covalent reactions that react reversibly under identical reaction conditions and do not exhibit any cross-reactivity. Dynamic behavior was shown via (1)H NMR based exchange experiments. Computational deconvolution of (1)H NMR spectra containing the components for more than one of the orthogonal reactions allowed for a semiquantitative analysis of the complex mixtures formed, showing that the reactions proceed independently of each other. Therefore, it is possible to use all four reactions in one pot in a simultaneous, yet orthogonal fashion. This opens up possibilities for the preprogrammed formation of complex thermodynamic assemblies.

This study describes synthetic efforts towards the molecular Borromean link consisting of three unequal rings. The design and strategy involve step by step construction of a ruthenium(II) templated ring-in-ring complex doubly threaded with endocyclic ligands ready for the macrocyclization. The control over the topology is achieved by using specially designed directional building blocks based on 2,2′:6′,2′′-terpyridine. Preliminary macrocyclization attempts utilizing the copper-mediated Eglington reaction provide the mass spectrometric evidence consistent with the ruthenium(II) complex of the molecular Borromean link.

A new method for lowering the error of CD based methods for measuring high enantiomeric excess values is described, which exploits the majority rules effect exhibited by certain helical polymers. A proof of principle experiment was conducted.

This chapter describes design concepts for synthetic receptors in supramolecular systems. The foundations of host:guest chemistry are first explored in the context of preorganization and complementarity, followed by discussions of the strength and solvent dependence of binding interactions. Reversible covalent interactions are then described, as are computational methods for predicting host:guest binding. Common synthetic receptor scaffolds such as crown ethers, calixarenes, calixpyrroles, cucurbiturils, and cyclodextrins are reviewed, and their binding properties are described. High-throughput methods, such as the design and use of combinatorial libraries and cross-reactive arrays, are detailed. Finally, thermodynamic concerns such as cooperativity and entropy–enthalpy compensation are discussed.