Anion‐Templated Synthesis

Abstract

In contrast to the well-studied templating properties of cationic and neutral species there are relatively few examples of anion-templated syntheses. This is attributed to some of the intrinsic properties of anions such as their diffuse nature, pH sensitivity, and their relative high solvation free energies. However, the increasing number of anion-templated assemblies reported over the past few years demonstrates that these limitations are not as critical as first thought. This review summarizes the most important results on the use of anions as directing agents for the syntheses of a wide range of inorganic and organic assemblies (such as macrocycles, cages, helicates, rotaxanes, and extended structures). It is hoped that this will stimulate a closer look into this emerging area of supramolecular chemistry.

Bridging ligands comprising two or more di-2-pyridylmethyl or amine arms: Alternatives to 2,2′-bipyridyl-containing bridging ligands

“…Where feasible and timely, the application of the resulting complex species is described to indicate the functional context guiding the design of the ligands discussed. Bridging ligands of the type covered in this review have featured as part of other review articles, on binucleating ligands, [18] ligand design, [7] starburst complexes, [19] cyclometallation, [20] spin-crossover systems, [21] cross-conjugated organic compounds [22] and anion templated synthesis, [23] for example.…”

Pre-organisation or a hydrogen bonding mismatch: silver(I) diamide ligand coordination polymers versus discrete metallo-macrocyclic assemblies

“…Strategies to selectively complex anions require the synthesis of hosts utilising one or more of a toolbox of interactions, 11 including hydrogen bonding donor groups, 10,12 π-acidic heteroarene scaffolds, [14][15][16][17] cationic groups for electrostatic interactions 11,18 and Lewis acidic moieties. 11 The investigation of metallo-supramolecular assemblies 5,[19][20][21][22] and coordination polymers [23][24][25] as anion receptors and for anion separation or sequestration has also received attention. In the context of developing such systems for anion inclusion, the use of a metallo-supramolecular species to bind anions can provide a number of advantages over neutral organic receptors.…”

Current status and challenges of ion imprinting

“…Powell et al 254 chose cyclic adenosine 3 0 :5 0 -monophosphate (cAMP) as a template. 255 They incorporated a uorescent dye as an integral part of the recognition cavity to obtain an extra signal by the change of luminescence. For pinacolyl methylphosphonate (PMP), the hydrolysis product of Soman used by Murray and his team, 225,256 was reversibly bound to ligand-coordinated Eu(III) as a template in the preparation of an imprinted polymeric luminescent sensor.…”