Oxidation of Benzylic Alcohols with I2/K2CO3/tert-butanol: Formation of Aldehydes or Dimeric Esters

Oxidation of a series of aromatic and heteroaromatic benzylic alcohols with molecular iodine in tert-butanol in the presence of potassium carbonate has been studied. Oxidation of most benzylic alcohols affords the corresponding aldehydes in reasonable yields. The reaction has been shown to be compatible with amino, formyl, methylthio groups and thiophene ring in the molecule. Oxidation of the electron-poor benzylic alcohols such as nitrobenzyl alcohols and (benzimidazol-2-yl)methanol results in the formation of the corresponding dimeric esters.