Supramolecular Chemistry

Abstract

Supramolecular chemistry has its origins in the supermolecule, a term used by Nobel Laureate Jean‐Marie Lehn from the early 1970s when referring to a well‐defined chemical species comprising several components. The realization that supermolecules could in turn form larger molecular assemblies led to the shift in emphasis from super‐ to supramolecular in the literature to more accurately describe the complexity of systems involved. Supramolecular chemistry has since advanced to include complexes between molecules with complementary binding sites (molecular recognition), multicomponent complexes (supramolecular assemblies), the programmed interactions between large molecular assemblies (molecular tectonics), and even the directed assembly of three‐dimensional solids (crystal engineering). This article sets out the concepts and aims of supramolecular chemistry, illustrates some of the early development in the field, considers the synthesis and structures of individual supramolecular synthons as well as supramolecular assemblies, and concludes with an assessment of current and anticipated applications in materials science, medicine, the interface with biology, molecular computing, nanomaterials, and nanomachines.

Metal compounds with rigid polyaromatic ligands. Catalytic consequences

“…68 Some authors have suggested that the contribution of the π-back donation present in the NHC-metal bonding has not been seen as significant with respect to σ-bonding. 69,70 However, some experimental and theoretical approaches [71][72][73][74][75][76] have demonstrated that the NHC can act as π-acceptor via back donation from the M(d π ) orbitals, especially in those complexes that contains electron-rich metals. 77,78 Several methods have been developed to quantify and compare the electronic properties of NHC ligands.…”

“…Cuando estos grupos se encuentran formando interacciones π−π o host/guest, las bandas de absorción son desplazadas como respuesta a dicha unión. 69 Nosotros realizamos los estudios de absorción de Uv-vis del complejo 7C y pireno en metanol a temperatura ambiente. Este estudio consiste en mantener la concentración fija de pireno mientras la concentración de 7C es aumentada gradualmente, esta metodología ha sido usada anteriormente para estudios similares.…”