Triethylamine → (4-Methylpiperazin-1-yl)acetic acid

Participants

Reaction Steps

A mixture of 1-methylpiperazine (10.7 g), benzylbromoacetate (24 g), triethylamine (28 ml) and dichloromethane (100 ml) was stirred at ambient temperature for 4 hours. The reaction was concentrated to dryness, taken up in tetrahydrofuran (100 ml), filtered, and the filtrate evaporated to dryness. The residue was taken up in methanol (100 ml), treated with aqueous sodium hydroxide solution (100 ml, 1M) and stirred at reflux for 24 hours. The reaction was concentrated to dryness, diluted with water (100 ml) and then acidified to pH6.0 by addition of concentrated hydrochloric acid. The mixture was evaporated.. A portion of the resulting brown oil (2.0 g) was taken up in water (100 ml), treated with Dowex 50WX8 resin (80 g) and stirred at ambient temperature for 10 minutes. The mixture was filtered and the resin washed with water until the washings were neutral. The resin was then stirred with 2.0M aqueous ammonia (3×100 ml) for 5 minutes and filtered. The combined ammonia washings were concentrated to leave the title compound as a white waxy solid (0.8 g).

Provenance & Evidence