Preparation of 1-alkyl- or 1-cycloalkylpiperazines
AssigneeBASF SE
InventorsHerbert Mueller, Dieter Voges, Wolfgang Lengsfeld
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Abstract
1-Alkyl- or 1-cycloalkylpiperazines are prepared by reacting piperazine with an alkanol or cycloalkanol in the presence of hydrogen and a hydrogenation/dehydrogenation catalyst by a process in which the reaction is carried out at from 130.degree. to 190.degree. C. under from 5 to 100 bar in the presence of from 5 to 40% by weight, based on the reaction mixture, of water, and the molar ratio of piperazine to alkanol or cycloalkanol is kept at from 1:1.5 to 1:8.
Claims6
A process for the preparation of a 1-alkyl-, 1-cycloalkylpiperazine or 1-piperazinly-3-tetrahydrofuranylmethane by reacting piperazine with an alkanol, cycloalkanol or 3-hydroxymethyltetrahydrofuran in the presence of hydrogen and a hydrogenation/hydrogenation catalyst, wherein the reaction is carried out at from 130.degree. to 190.degree. C. and under from 5 to 100 bar in the presence of from 5 to 40% by weight, based on the reaction mixture, of water which is added to the reaction mixture, and in the presence of from 0.01 to 1% by weight, based on the reaction mixture, of an inorganic base, and the molar ratio of piperazine to alkanol, cycloalkanol or 3-hydroxymethyltetrahydrofuran is kept at from 1:1.5 to 1:8.
Dependencies are inferred from the claim text.