Benzenebutanol → 4-Phenylbutanal

To a solution of 3.2 mL (20.8 mmol) of 4-phenyl-1-butanol (Aldrich Chemical Co.) in 20 mL of CH2Cl2 at 0° C. was added 3.2 g of powdered 3 Å molecular sieves and then 5.37 g (24.9 mmol) of pyridinum chlorochromate (PCC). The resulting suspension was stirred at 0° C. for 1 h at which time an additional 2.16 g (10.0 mmol) of PCC was added and the reaction mixture was warmed to room temperature. After stirring at ambient temperature for 0.5 h, the reaction mixture was diluted with ether and filtered through celite to give 2.5 g of the crude product. Flash chromatography (elution with 5% ethyl acetate in hexane) yielded 700 mg of the aldehyde 119. 1H NMR was consistent with the structure.