公开(公告)号：US3607874A

公开(公告)日：1971-09-21

申请号：US3607874D

申请日：1968-11-21

Applicant: BASF AG

Inventor： FUERST ERNST ,  TOUSSAINT HERBERT ,  SOLD GEORG

IPC: C07D295/023 ,  C07D51/66

CPC classification number: C07D295/023 ,  Y02P20/582

Abstract: Production of N-methylpiperazine by reaction of aqueous formaldehyde solution with piperazine followed by hydrogenation of the polymethylenepiperazine formed in the presence of known hydrogenation catalysts at superatmospheric pressure and elevated temperature, the reaction being carried out in the presence of acetic acid or piperazine acetate and the N,N''-dimethylpiperazine formed during the hydrogenation being distilled off as an azeotrope with water. N-methylpiperazine is used as a selective solvent for the extraction of aromatics from hydrocarbon mixtures.