Probing Through-Space Polar-π Interactions in 2,6-Diarylphenols.

Although it is well established that the acidity of phenol can be fine-tuned with substituents on its aromatic ring via through-bond effects, the role of through-space effects on the acidity of phenols is presently poorly understood. Here, we present integrated experimental and computational studies on substituted 2,6-diarylphenols that demonstrate the essential contribution from through-space OH-π interactions and O--π interactions in the observed trends in proton affinities and acidities of 2,6-diarylphenols.