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.

A A r ra ar re e c ca as se e o of f i in nf fl la am mm ma at to or ry y p ps se eu ud do ot tu um mo ou ur r o of f t th he e b br ro on nc ch hu us s, , o oc cc cu ur r--r ri in ng g i in n a an n a ac ch ho on nd dr ro op pl la as st ti ic c w wo om ma an n M. Vanderheyden*, J. Van Meerbeeck**, E. Van Bouwel*, V. Bosmans*, C. Colpaert***, M. Ramael**