Sodium Carbonate → (3aRS,5RS,7aRS)-5-acetoxy-2-benzyl-7,7-diphenylperhydro-4-isoindolone

Participants

Reaction Steps

To a solution of 86 g of 6-acetoxy-4,4-diphenyl-2-cyclohexenone and 96 cm3 of N-butoxymethyl-N-(trimethylsilylmethyl)benzylamine in 1000 cm3 of dichloromethane are added 15 drops of trifluoroacetic acid. The reaction mixture is stirred at room temperature for 15 hours, followed by addition of 2 g of sodium carbonate and concentration to dryness under reduced pressure (2.7 kPa). The residue is chromatographed on a column of Merck silica gel (particle size 0.04-0.06 mm, diameter 7 cm, height 70 cm), eluting under a nitrogen pressure of 50 kPa with a mixture of cyclohexane and ethyl acetate (20/80 by volume) and collecting 200 cm2 fractions. Fractions 6 to 10 are combined and concentrated to dryness under reduced pressure (2.7 kPa). 70 g of (3aRS,5RS,7aRS)-5-acetoxy-2-benzyl-7,7-diphenylperhydro-4-isoindolone in the form of a syrup are obtained (melting point below 40° C.).

Provenance & Evidence