Reagents and Procedures for Alcohol Oxidation

Chromic acid oxidation may also be performed in the presence of water-immiscible solvents. Addition of a stoichiometric amount of aqueous sodium dichromate and sulfuric acid to a solution of the secondary alcohol in diethyl ether at 25 °C affords the corresponding ketone.  

Primary and secondary alcohols are readily oxidized in CH2CI2 utilizing 1 to 1.5 equivalents of PCC. Since PCC is slightly acidic, oxidations of compounds containing acid-sensitive groups should be carried out in the presence of powdered 

Oxidation of primary alcohols with PCC in the presence of molecular sieves (3 A or 4 A) results in higher yields of aldehydes. Ultrasound also has been used to facilitate PCC oxidations.  

In DMF solution, however, PDC oxidizes nonconjugated primary alcohols to the corresponding carboxylic acids.Oxidations of 2° alcohols by PDC in DMF proceed to give the corresponding ketones. 

The Swern oxidation proceeds rapidly at low temperatures and thus can be employed for the preparation of a-keto aldehydes and acylsilanes, which are hyperactive carbonyl compounds and prone to hydration, polymerization, and air oxidation.  

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