p-Toluenesulfonic acid → HCID 53687538, compound

Participants

Reaction Conditions

Reaction Steps

8.8 g (0.025 mole) of the 1-(3,5-bis-trifluoromethylphenyl)-2-oxo-pyrrolidine-4-carboxylic acid produced according to Example 1 is refluxed together with 0.3 g of p-toluenesulphonic acid in 130 ml of absolute methanol, and the reaction mixture is kept at this temperature during 17 hours. It is subsequently cooled to 20° C and 0.1 g of sodium carbonate is added. Excess methanol is evaporated off. The residue is dissolved in diethyl ether, extracted three times with water, dried, and concentrated by evaporation. By recrystallisation from n-hexane there is obtained 8.4 g (91% of theory) of 1-(3,5-bis-trifluoromethylphenyl)-2-oxo-pyrrolidine-4-carboxylic acid methyl ester; m.p. 68°-70° C. Analysis for C14H11F6NO3 (molar weight 355.17):

Provenance & Evidence