METHOD OF PREPARING 1-NITROSO-4-METHYLPIPERAZINE Russian patent published in 1997 - IPC

FIELD: chemistry of drugs as intermediate product in synthesis of amino-4-methylpiperazine and 1-methylpiperazine. SUBSTANCE: desired product is prepared by nitriding piperazine-dichlorohydrate with sodium nitrite at 6-30 C, and subsequent methylation of 1-nitropiperazine is carried out at 6-7 directly in reaction mixture. Its composition is corrected, if desired, by filtration or addition of 1,4-dinitrosopiperazine (wt %); 1.0-23.0 1,4- dinitroso piperazine; 2.0-5.0 piperazine; 75.0-94.0 1- nitropiperazine, generally at 80-100 C and 1- nitrosopiperazine to formaldehyde molar ratio of 1.0- 1.8-2. EFFECT: more efficient preparation method. 14 cl, 2 dwg