Benzaldehyde → cis-1-Benzyl-3-benzylaminomethyl-4-methylpyrrolidine

Participants

Reaction Steps

cis-1-Benzyl-4-methyl-3-aminomethylpyrrolidine (1000 mg) was dissolved in methanol (10 mL). While this solution was chilled in an ice water bath, benzaldehyde (0.50 mL) was added dropwise and the mixture was stirred at room temperature for 1 hour. Subsequently, sodium cyanoborohydride (184 mg) was added and the mixture was stirred at room temperature for 1.5 hours, followed by addition of a second portion of sodium cyanoborohydride (123 mg) and then further stirring for 5.5 hours. To the resulting mixture, a 2 mol/L aqueous solution of sodium hydroxide (5 mL) was added and the mixture was refluxed for 2 hours. Subsequently, the reaction mixture was concentrated under reduced pressure and the residue was extracted with toluene (2×30 mL). The toluene layers were combined, washed with water, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane: ethyl acetate=4:1) to give cis-1-benzyl-3-benzylaminomethyl-4-methylpyrrolidine as a pale yellow oil (690 mg).

Provenance & Evidence