The search for the gas‐phase negative‐ion pinacol rearrangement. 2—aryl rearrangements

Abstract

Deprotonated phenyl ethylene glycols, on collisional activation, lose water by a negative ion pinacol rearrangement involving phenyl migration. For example, deprotonated benzpinacol undergoes the following reaction:Ph,C(OH)C(O-)Ph, + (PhCOCPh, -HI-+ H,O. It is proposed that this rearrangement proceeds from an eclipsed (or near eclipsed) conformer which is stabilized by the HO and 0groups forming a strong intramolecular hydrogen bond.