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Lehn J.-M.,CNRS Institute of Science and Supramolecular Engineering
Angewandte Chemie - International Edition

(Figure Presented). Chemistry, pure and applied, is a science and an industry. By its power over the expressions of matter, it also displays the creativity of art. It has expanded from molecular to supramolecular chemistry and then, by way of constitutional dynamic chemistry, towards adaptive chemistry. Constitutional dynamics allow for adaptation, through component exchange and selection in response to physical stimuli (e.g. light, photoselection), to chemical effectors (e.g. metal ions, metalloselection) or to environmental effects (e.g. phase change) in equilibrium or out-of-equilibrium conditions, towards the generation of the best-adapted/fittest constituent(s) in a dynamic set. Such dynamic systems can be represented by two-dimensional or three-dimensional dynamic networks that define the agonistic and antagonistic relationships between the different constituents linked through component exchange. The introduction of constitutional dynamics into materials science opens perspectives towards adaptive materials and technologies, presenting attractive behavioral features (such as self-healing). In particular, dynamic polymers may undergo modification of their properties (mechanical, optical, etc.) through component exchange and recombination in response to physical or chemical agents. Constitutional adaptive materials open towards a systems materials science and offer numerous opportunities for soft-matter technologies. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Source

Lehn J.-M.,CNRS Institute of Science and Supramolecular Engineering
Topics in Current Chemistry

Supramolecular chemistry aims at implementing highly complex chemical systems from molecular components held together by non-covalent intermolecular forces and effecting molecular recognition, catalysis and transport processes. A further step consists in the investigation of chemical systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, thus behaving as programmed chemical systems. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels. CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation. The merging of the features: -information and programmability, -dynamics and reversibility, -constitution and structural diversity, points to the emergence of adaptive and evolutive chemistry, towards a chemistry of complex matter. © 2011 Springer-Verlag Berlin-Heidelberg. Source

Biedermann F.,CNRS Institute of Science and Supramolecular Engineering | Nau W.M.,Jacobs University Bremen | Schneider H.-J.,Saarland University
Angewandte Chemie - International Edition

Traditional descriptions of the hydrophobic effect on the basis of entropic arguments or the calculation of solvent-occupied surfaces must be questioned in view of new results obtained with supramolecular complexes. In these studies, it was possible to separate hydrophobic from dispersive interactions, which are strongest in aqueous systems. Even very hydrophobic alkanes associate significantly only in cavities containing water molecules with an insufficient number of possible hydrogen bonds. The replacement of high-energy water in cavities by guest molecules is the essential enthalpic driving force for complexation, as borne out by data for complexes of cyclodextrins, cyclophanes, and cucurbiturils, for which complexation enthalpies of up to -100 kJ mol-1 were reached for encapsulated alkyl residues. Water-box simulations were used to characterize the different contributions from high-energy water and enabled the calculation of the association free enthalpies for selected cucurbituril complexes to within a 10 % deviation from experimental values. Cavities in artificial receptors are more apt to show the enthalpic effect of high-energy water than those in proteins or nucleic acids, because they bear fewer or no functional groups in the inner cavity to stabilize interior water molecules. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Hardy J.G.,CNRS Institute of Science and Supramolecular Engineering | Hardy J.G.,University of Texas at Austin
Chemical Society Reviews

Metallosupramolecular grid complexes (hereafter referred to as metallogrids) are well-defined oligonuclear metal ion complexes involving essentially planar arrays of the metal ions sited at the points of intersection of square or rectangular metallogrids and possess a variety of interesting optical, electronic, magnetic and supramolecular properties. Herein I aim to give the reader an overview of the synthesis, properties and potential for a variety of high-tech applications of metallogrids. This journal is © The Royal Society of Chemistry. Source

Harrowfield J.,CNRS Institute of Science and Supramolecular Engineering
Chemical Communications

The synthesis in 1985 by the group led by Tony McKervey of numerous calix[4]arene derivatives capable of acting as neutral, multidentate ligands proved to be a seminal step in the development of various applications of calixarenes as metal-ion binding agents. This journal is © The Royal Society of Chemistry 2013. Source

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