Electrooxidative coupling of phenols. I. Product-selective electrosynthesis of 2,2′,6,6′-tetra-tert-butyl-1,1′-biphenol from 2,6-Di-tert-butylphenol

Abstract Biphenol electrosynthesis is achieved in a divided cell by a set of redox reactions from 2,6-di- tert -butylphenol (4) via the corresponding diphenoquinone 3. Phenol 4 can also lead to either the corresponding biphenol 2 or diphenoquinone 3 in a product-selective manner by electrooxidation in an undivided cell. The choice of solvent is a crucial factor for the product-selectivity.