Novel and Selective Method for the Aerobic Oxidation of Benzylic Alcohols in the Absence of Metal Catalyst

Abstract

A metal-free aerobic oxidation of benzylic alcohols to the corresponding benzylaldehyde derivatives was accomplished using proton ionic liquids (pyridium nitrate) as catalyst in a nonsolvent system with excellent conversion and selectivity. The catalyst could be recycled with no other polluted emission in this reaction procedure.

Aerobic Oxidation Catalysis with Air or Molecular Oxygen and Ionic Liquids

“…This catalytic system could also be used for the oxidative cross‐esterification of primary benzyl alcohols with a higher aliphatic alcohol. Also, a metal‐free aerobic oxidation of benzylic alcohols was carried out with proton ILs (pyridium nitrate) as catalyst in a solvent‐free system with excellent conversion and selectivity 79. Very recently, a novel temperature‐dependent IL catalytic system based on TEMPO and PEG 600 (polyethylene glycol 600) with cyclohexane, CCl 4 , NaNO 2 and O 2 has been introduced for the aerobic oxidation of a variety of alcohols into their corresponding aldehydes or ketones with good yield and selectivity 80.…”