Study on the Synthesis Method of N-Methylpiperidine
Objective:To establish a synthesis method of N-methylpiperidine and to investigate the effect of synthesis conditions on its content.Methods:Using piperidine and formaldehyde as raw materials,sodium formate and formic acid as reducing agents,N-methylpiperidine solution was obtained by alkylation,and then N-methylpiperidine was obtained by cyclohexane extraction and rectification.Results:The N-methylpiperidine content was 99.1%under the optimal conditions of 1∶1.2∶1.2,droplet acceleration of 3.33 mL/min,dropping time of 60 min and reaction temperature of 80℃for 3 h,and the content of N-methylpiperidine was 99.1%,and the content was 99.5%and the yield was 98.7%after cyclohexane extraction and distillation.Conclusion:The reaction conditions of this method are mild,the product purity is high,the process is simple,and it is easy to realize industrialization.