Vinyl chloroformate → (3aRS,7aRS)-7,7-bis(3-chlorophenyl)-2-vinyloxycarbonylperhydro-4-isoindolone

Participants

Reaction Steps

A solution of (3aRS,7aRS)-2-benzyl-7,7-bis-(3-chlorophenyl)-4-perhydroisoindolone (11.5 g) in 1,2-dichloroethane (250 cc) is treated with vinyl chloroformate (2.8 cc) and refluxed for 16 hours and then concentrated under reduced pressure (2.7 kPa). The residue is chromatographed on a silica gel column (particle size 0.04-0.063 mm, diameter 6 cm, height 32 cm), eluting under a nitrogen pressure of 0.5 bar with a mixture of cyclohexane and ethyl acetate (80/20) and collecting 25 cc fractions. Fractions 19 to 27 are combined and concentrated to dryness under reduced pressure (2.7 kPa). The meringue obtained is solidified in isopropyl ether and the precipitate is drained, washed with isopropyl ether and dried to give (3aRS,7aRS)-7,7-bis-(3-chlorophenyl)-2-vinyloxycarbonyl-4-perhydroisoindolone (6.7 g) in the form of a white solid.

Provenance & Evidence