2-Methoxyphenylacetic acid → (3aRS,7aRS)-7,7-Diphenyl-2-[(2-methoxyphenyl)acetyl]perhydro-4-isoindolone

Participants

Reaction Steps

N,N'-Carbonyldiimidazole (1.13 g) is added to a solution of 2-methoxyphenylacetic acid (1.16 g) in dry dichloromethane (30 cc), cooled to +5° C. The mixture is stirred for 15 minutes at +5° C. and a solution of (3aRS,7aRS)-7,7-diphenyl-4-perhydroisoindolone hydrochloride (2.28 g) and triethylamine (1.96 cc) in dichloromethane (20 cc) is then added. The reaction mixture is stirred at 20° C. for 16 hours, then washed with water (2×150 cc), dried over magnesium sulphate and filtered and the filtrate is concentrated to dryness under reduced pressure (2.7 kPa). The meringue obtained is crystallized from a mixture of acetonitrile (30 cc) and isopropyl ether (80 cc). The crystals are drained, washed with isopropyl ether and dried. (3aRS,7aRS)-7,7-diphenyl-2-[(2-methoxyphenyl)-acetyl]-4-perhydroisoindolone (2 g) is obtained in the form of white crystals melting at 158° C.

Provenance & Evidence