2,2'-Biphenol


2,2′-Biphenol is an organic compound with the formula 2. It is one of three symmetrical isomers of biphenol. A white solid, it is a precursor to diphosphite ligands that are used to support industrial hydroformylation catalysis.
image:BiPhePhos.svg|thumb|244px|left|BiPhePhos is representative diphosphite ligand derived from a derivative of 2,2′-biphenol.

Synthesis

2,2′-Biphenol can be made by hydrolysis of dibenzofuran. Alternatively, it can be produced from 2,4-di-tert-butylphenol in two steps. The first step entails oxidative coupling to give the 2,2′-biphenol with four tert-butyl substituents. Upon heating, this species then undergoes debutylation.