Potassium Carbonate → (3aRS, 7aRS)-2-benzyl-7,7-diphenyl-4-perhydroisoindolone

Participants

Reaction Conditions

Reaction Steps

Trifluoroacetic acid (5 drops) is added to a solution of 4,4-diphenyl-2-cyclohexen-1-one (155 g) and N-butoxymethyl-N-(trimethylsilylmethyl)benzylamine (202 cc) in dry dichloromethane (1000 cc), and the reaction mixture is heated to reflux for 45 minutes. N-Butoxymethyl-N-(trimethylsilylmethyl)benzylamine (50 cc) and trifluoroacetic acid (3 drops) are added and the mixture is stirred for a further 45 minutes under reflux before N-butoxymethyl-N-(trimethylsilylmethyl)benzylamine (25 cc) and trifluoroacetic acid (3 drops) are added again. The reaction mixture is stirred under reflux for 45 minutes, then treated with potassium carbonate (50 g), filtered and concentrated to dryness under reduced pressure (2.7 kPa). The residue is dissolved in isopropyl ether (200 cc) and the solution cooled to 0° C. for 1 hour. The crystals are drained, washed with isopropyl ether (2×15 cc) and dried to give (3aRS,7aRS)-2-benzyl-7,7-diphenylperhydro-4-isoindolone (193 g) in the form of white crystals, m.p. 132° C.

Provenance & Evidence