2-Cyclohexen-1-one, 4,4-diphenyl- → (3aRS, 7aRS)-2-benzyl-7,7-diphenyl-4-perhydroisoindolone

Participants

Reaction Steps

A solution of 4,4-diphenyl-2-cyclohexen-1-one (25 g) and 3-benzyl-5-oxazolidone (2.5 g) in dry toluene (100 cc) is heated to reflux for 2 hours 30 minutes. The reaction mixture is concentrated to dryness under reduced pressure (2.7 kPa). The residue is chromatographed on a column of silica gel (0.2-0.063 mm, diameter 4.5 cm, height 23 cm), eluting under a nitrogen pressure of 0.5 bar with a mixture of cyclohexane and ethyl acetate (80:20 by volume) and collecting 50-cc fractions. Fractions 13 to 17 are combined and concentrated to dryness under reduced pressure (2.7 kPa) to give (3aRS,7aRS)-2-benzyl-7,7-diphenylperhydro-4-isoindolone (0.9 g) in the form of white crystals, m.p. 132° C.

Provenance & Evidence