1-chloro-1,1-difluoro-4-phenylbutan-2-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Add titanium tetrachloride (0.019 g, 0.1 eq) to a suspension of activated zinc (0.196 g, 3mAtg) in anhydrous THF (3 mL) at 0° C. under nitrogen. Stir 30 minutes and add CBz(L)-Val-Phe-H (0.42 g, 1.1 mmol), 1-chloro-1,1-difluoro-2-oxo-4-phenylbutane (0.218 g, 1.1 mmol), in anhydrous THF (4 mL). Allow the reaction to warm to room temperature and stir for 12 hours. Add a saturated solution of ammonium chloride (2 mL). Extract two times with diethyl ether (4 mL) and wash the organic phase with brine and dry over anhydrous magnesium sulphate. Concentrate the organic phase under vacuum. Purify the crude residue by flash chromatography (silica gel, 3:7 ethyl acetate:cyclohexane) to provide the title alcohol (0.381 g). the reaction stir for 12 hours Extract two times with diethyl ether (4 mL) wash the organic phase with brine dry over anhydrous magnesium sulphate Concentrate the organic phase under vacuum Purify the crude residue by flash chromatography (silica gel, 3:7 ethyl acetate:cyclohexane)