Measuring anion-π interactions

Anion–π interactions influence pK a values

Five 8-(4-R-phenyl)-1-naphthol derivatives were prepared by PdCl(2)-catalysed electrophilic aromatic substitution. The pK(a)' values for these 1,8-disubstituted arene naphthols have been measured in acetonitrile/water (R = NO(2), 8.42; R = Cl, 8.52; R = H, 8.56; R = Me 8.68; and R = OMe, 8.71) and indicate a correlation with the electronic nature of the arene substituent, as determined through ...

Towards design strategies for anion–π interactions in crystal engineering

Anion-π Enzymes

In this report, we introduce artificial enzymes that operate with anion-π interactions, an interaction that is essentially new to nature. The possibility to stabilize anionic intermediates and transition states on an π-acidic surface has been recently demonstrated, using the addition of malonate half thioesters to enolate acceptors as a biologically relevant example. The best chiral anion-π cat...

Novel Noncovalent Interactions in Catalysis: A Focus on Halogen, Chalcogen, and Anion-π Bonding

Noncovalent interactions play an important role in many biological and chemical processes. Among these, hydrogen bonding is very well studied and is already routinely used in organocatalysis. This Short Review focuses on three other types of promising noncovalent interactions. Halogen bonding, chalcogen bonding, and anion-π bonding have been introduced into organocatalysis in the last few years...

Photomodulation of fluoride ion binding through anion-π interactions using a photoswitchable azobenzene system

The discovery of photoswitchable azobenzene-systems that undergo trans-to-cis photoisomerisation was a milestone in supramolecular chemistry. Such photoswitches have possible applications in data storage, stimuli responsive delivery systems, and molecular machines due to fast and selective switching. However, the light induced cis isomer of azobenzene is rather unstable and reverts thermally an...