NOTE: manganese dioxide is selective for the oxidation of benzyl and allyl alcohols to the corresponding aldehyde
To a solution of the alcohol in CHCl3 (10 mL/mmol) is added activated manganese dioxide (2 g/mmol), and the resultant mixture is stirred at room temperature for 2h. The reaction mixture is filtered and washed with chloroform. The combined filtrate is concentrated to give the aldehyde. Yield: Fair-Good.