Ethanol → 1,4-Dimethylpiperazine

Participants

Reaction Steps

A solution of 86 g. (1.0 mole) of piperazine in 262 g. ethanol was added with stirring to 130 g. (1.6 moles) of 37% formalin in an appropriate vessel at a temperature of 30°-40°C. maintained with cooling. This slurry, containing 25 wt.% water and 75 wt.% ethanol as solvent, based on solvent weight, was then charged to an autoclave containing 14 g. of a supported nickel catalyst (Harshaw Ni-3266P, Harshaw Chemical Company) and stirred in a hydrogen atmosphere at 91°C. under 50 psig for 5 hours. Analysis of the crude product by gas liquid chromatography, calculating on a water-alcohol free basis, gave 60.4% 1,4-dimethylpiperazine, 38.2% 1-methylpiperazine, and 0.5% piperazine.

Provenance & Evidence