Benzhydrol is oxidized to benzophenone, by sodium hypochlorite (commonly known as bleach) in the presence of a phase-transfer catalyst.
Synthesis: In a 20-mL green capped vial, place 1.5 mL of ethyl acetate, 100 mg (0.54 mmol) of benzhydrol and a few drops of methyltricaprylammonium chloride solution (Stark's catalyst or tricaprylmethylammonium chloride). Add a half-inch magnetic stirring bar, and stir until all reagents are dissolved. Cool the solution in an ice bath and add 2 mL of 5% NaOCl (aq) (bleach) dropwise using a 2.5- mL syringe. After the addition of the hypochlorite is complete, allow the reaction to stir for five minutes in the ice-water bath and then stir for a period of one hour at room temperature.
Reduction of benzophenone to benzhydrol.
4MPDC (4-Methyl pyridinium di chromate) is used as oxidizing agent to oxidize benzhydrol. PDC is a mild and selective oxidizing agent and is soluble in water and many organic solvents. Therefore, advantage over inorganic dichromate.
