O-Toluidine → N-(2-methylphenyl)-4-methylvaleramide

Participants

Reaction Steps

Carbonyldiimidazole (65 g) was mixed with 500 ml of dry dichloromethane in a 2-L round bottom flask and stirred magnetically. A solution of 4-methylvaleric acid in 200 ml of dichloromethane was added dropwise over 45 minutes and the mixture was stirred for another 1.25 hours. o-Toluidine (45 g) in 100 ml of dichloromethane was then added over about 20 minutes. After stirring for 2 hours the mixture was washed with water and then the solvent was stripped on a rotary evaporator. The residue was mixed with 150 ml of methanol and 75 ml of water and put in the freezer. Filtration of the precipitate, dilution of the filtrate with water and refiltration of the precipitate gave 75 g (94%) of vacuum dried N-(2-methylphenyl)-4-methylvaleramide which was used without further treatment in the next step:

Provenance & Evidence