1，2，2，6，6-五甲基哌啶醇是合成受阻胺光稳定剂的重要中间体。以2，2，6，6-四甲基哌啶醇、多聚甲醛和甲酸为原料，水为溶剂，经还原甲基化反应合成了1，2，2，6，6-五甲基哌啶醇，并通过核磁共振氢谱、碳谱和红外光谱对产物结构进行了表征。单因素实验和正交实验结果表明，原料摩尔比对还原甲基化反应的影响最大，其次是反应温度，最后是反应时间。该还原甲基化反应适宜条件为：n（四甲基哌啶醇）：n（多聚甲醛）：n（甲酸）=1：1.05：1.05、反应温度为80℃、反应时间为2.5 h，溶剂水可以套用3次。在此优化条件下，产品平均收率为97.9%，纯度为99.6%。

1,2,2,6,6-Pentamethylpiperidinol is an important intermediate for the synthesis of hindered amine light stabilizers (HALS).1,2,2,6,6-Pentamethylpiperidinol is synthesized by reductive methylation from 2,2,6,6-tetramethylpiperidinol,paraformaldehyde and formic acid in water.Its structure is characterized by ¹HNMR,¹³CNMR and FT-IR.From the single factor experiments and orthogonal experimental results,it is known that the molar ratio of raw materials has the biggest influence on the reductive methylation reaction,followed by the reaction temperature,and finally the reaction time.The optimal methylation conditions are as follows,n(tetramethylpiperidinol):n(paraformaldehyde):n(formic acid)=1:1.05:1.05,the reaction temperature is at 80℃,reaction time is 2.5 h,and solvent water can be recovered and recycled for 3 times.Under these optimized conditions,the average yield of the desired product is 97.9% with a purity of 99.6%.

严宁宁(1993-),女,硕士研究生,研究方向为精细化学品的合成,390715067@qq.com