RESUMO
A rigid organic ligand, formed through the subcomponent self-assembly of p-toluidine and 6,6'-diformyl-3,3'-bipyridine, was employed in a systematic investigation into the synergistic and competing effects of metal and anion templation. A range of discrete and polymeric metal-organic complexes were formed, many of which represent structure types that have not previously been observed and whose formation would not be predicted on taking into account solely geometric considerations. These complex structures, capable of binding multiple guests within individual binding pockets, were characterized by NMR, ESI-MS, and single-crystal X-ray diffraction. The factors that stabilize individual complexes and lead to the formation of one over another are discussed.
Assuntos
Complexos de Coordenação/química , Metais Pesados/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Differential binding affinities for a set of anions were observed between larger (1) and smaller (2) tetrahedral metal-organic capsules in solution. A chemical network could thus be designed wherein the addition of hexafluorophosphate could cause perchlorate to shift from capsule 2 to capsule 1 and triflimide to be ejected from capsule 1 into solution.
RESUMO
We report a short synthetic route for the preparation of a peptidic Au(I)-metalloamphiphile which, in buffered environments of physiological ionic strength, self-assembles into luminescent micellar nanostructures of 14 nm in diameter.
Assuntos
Ouro/química , Luminescência , Micelas , Peptídeos/síntese química , Tensoativos/síntese química , Água/química , Estrutura Molecular , Tamanho da Partícula , Peptídeos/química , Propriedades de Superfície , Tensoativos/químicaRESUMO
Biochemical systems are adaptable, capable of reconstitution at all levels to achieve the functions associated with life. Synthetic chemical systems are more limited in their ability to reorganize to achieve new functions; they can reconfigure to bind an added substrate (template effect) or one binding event may modulate a receptor's affinity for a second substrate (allosteric effect). Here we describe a synthetic chemical system that is capable of structural reconstitution on receipt of one anionic signal (perchlorate) to create a tight binding pocket for another anion (chloride). The complex, barrel-like structure of the chloride receptor is templated by five perchlorate anions. This second-order templation phenomenon allows chemical networks to be envisaged that express more complex responses to chemical signals than is currently feasible.