ピペラジン類の合成研究 (第4報)

β-アミノエタノール及びβ-アルキルアミノエタノールよりピペラジン類の合成

抄録

Heating of β-aminoethanol as a hydrochloride or hydrobromide for 1.5-3.5hours at 240-250° results in the formation of piperazine in 44-51% yield of the theoretical amount and a small amount of β, β′-diaminodiethyl ether (2-5% of the theoretical yield) is formed as a by-product. Heating of β-methylaminoethanol hydrochloride under the same conditions affords N-methylpiperazine (yield, 26%), N, N′-dimethylpiperazine (yield, 5%), and N, N′-dimethylethylenediamine (yield, 12%). The same reaction of β-dimethylaminoethanol gives only N, N′-dimethylpiperazine (yield, 26%). In the case of β-aminoethanol and mono-, di-, or trialkylamine hydrochloride gives, according to reaction conditions, N-alkyl- or N-dialkylethylenediamine and N-alkylpiperazine. In the case of β-aminoethanol and aromatic amines, only N-arylethyl enediamine is formed and N-arylpiperazine is not obtained. Catalytic vapor phase reactions of the above substances were not successful.