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Self-sorting phenomena are the basis of manifold relevant (bio)chemical processes where a set of molecules is able to interact with no interference from other sets and are ruled by a number of codes that are programmed in molecular structures. In this work, we study, the relevance of chelate cooperativity as a code for achieving high self-sorting fidelities. In particular, we establish qualitative and quantitative relationships between the cooperativity of a cyclic system and the self-sorting fidelity when combined with other molecules that share identical geometry and/or binding interactions. We demonstrate that only systems displaying sufficiently strong chelate cooperativity can achieve quantitative narcissistic self-sorting fidelities either by dictating the distribution of cyclic species in complex mixtures or by ruling the competition between the intra- and intermolecular versions of a noncovalent interaction.

Supramolecular ring-versus-chain equilibria are ubiquitous in biological and synthetic systems. Understanding the factors that decide whether a system will fall on one side or the other is crucial to the control of molecular self-assembly. This work reports results with two kinds of dinucleoside monomers, in which the balance between closed cycles and open polymers is found to depend on subtle factors that rule conformational equilibria, such as steric hindrance, intramolecular interactions, or π-conjugation pathways., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Self-assembled systems rely on intramolecular cooperative effects to control their growth and regulate their shape, thus yielding discrete, well-defined structures. However, as the size of the system increases, cooperative effects tend to dissipate. We analyze here this situation by studying a set of oligomers of different lengths capped with guanosine and cytidine nucleosides, which associate in cyclic tetramers by complementary Watson-Crick H-bonding interactions. As the monomer length increases, and thus the number of C(sp)-C(sp 2 ) σ-bonds in the π-conjugated skeleton, the macrocycle stability decreases due to a notable reduction in effective molarity (EM), which has a clear entropic origin. We determined the relationship between EM or ΔS and the number of σ-bonds, which allowed us to predict the maximum monomer lengths at which cyclic species would still assemble quantitatively, or whether the cyclic species would not able to compete at all with linear oligomers over the whole concentration range., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Herein, we analyze the intrinsic chelate effect that multipoint H-bonding patterns exert on the overall energy of dinucleoside cyclic systems. Our results indicate that the chelate effect is regulated by the symmetry of the H-bonding pattern, and that the effective molarity is reduced by about three orders of magnitude when going from the unsymmetric ADD-DAA or DDA-AAD patterns to the symmetric DAD-ADA pattern., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The preparation and self-assembly of novel G-C dinucleoside monomers that are equipped with electron-poor aryl groups at the G-N(2) amino group have been studied. Such monomers associate via Watson-Crick H-bonding into discrete unstrained tetrameric macrocycles that arise as a thermodynamically and kinetically stabilized product in a wide variety of experimental conditions, including very polar solvent environments and low concentrations. G-arylation produces an increased stability of the cyclic assembly, as a result of a subtle interplay between enthalpic and entropic effects involving the solvent coordination sphere.

A hydrogen-bonded cyclic tetramer is assembled with remarkably high effective molarities from a properly designed dinucleoside monomer. This self-assembled species exhibits an impressive thermodynamic and kinetic stability and is formed with high fidelities within a broad concentration range., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)