Triacetoxyperiodinane → 6-(4-tert-butylbenzoyl)-5-(4-fluorophenyl)-7-isopropyl-2,2-dimethyl-2,3-dihydro-4H-chromen-4-one

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Reaction Steps

At 0° C., 340 mg (800 μmol) of 1,1-dihydro-1,1,1-triacetoxy-1,2-benziodoxol-3(1H)-one are added to a solution of 190 mg (400 μmol) of a 2:1 mixture of rac-6-[(4-tert-butylphenyl)(hydroxy)-methyl]-5-(4-fluorophenyl)-7-isopropyl-2,2-dimethyl-2,3-dihydro-4H-chromen-4-one (Example 27A) and rac-6-[(4-tert-butylphenyl)(hydroxy)methyl]-5-(4-fluorophenyl)-7-n-propyl-2,2-dimethyl-2,3-dihydro-4H-chromen-4-one in 7.5 ml of dichloromethane, and the mixture is stirred at this temperature for 4 h. The mixture is then diluted with dichloromethane and washed three times with 1 M aqueous sodium hydroxide solution. The organic phase is dried over magnesium sulfate and then concentrated under reduced pressure, and the residue is purified by preparative HPLC (method 1) and subsequent column chromatography on silica gel (mobile phase: gradient cyclohexane→cyclohexane/dichloromethane/ethyl acetate 20:20:0.5).

Provenance & Evidence