薄层色谱法分离分析N,N-双(2,2,6,6-四甲基-4-哌啶)己二胺产物

TLC ANALYSIS OF REACTION PRODUCTS IN THE PREPARATION OF PIPERIDYLAMINE

研究了用薄层色谱法分离分析N,N 双(2,2,6,6 四甲基 4 哌啶)己二胺(简称哌啶胺)。该方法使用环己烷∶氨水∶甲醇∶乙醇∶异丙醇=2∶3∶4∶7∶8(V/V)为流动相(展开剂)、硅胶G为固定相、碘为显色剂,对哌啶胺的产物进行分离、分析,测定结果最小的ΔRf>0.06。该方法较高效液相色谱法方便、简单,且费用低,试样不用作任何处理,分析结果可用来指导哌啶胺的合成研究和工业化生产。

Piperidone, hexamethylenediamine (the reactants), N-(2,2,6,6-tetramethyl-4-piperidyl)-hexamine (the intermediate), N,N′-bis (2,2,6,6-tetramethyl-4-piperidyl)-hexamine (the objective product) and piperidinol (the by-product) were separated and determined by TLC. A mixture containing cyclohexane, aqueous ammonia, methanol, ethanol, iso-propanol in the ratio of 2∶3∶4∶7∶8 by volume was used as mobile phase, and silica gel G was used as the stationary phase. Development of the chromatogram by iodine vapor was found to be more feasible. A minimum ΔR_f greater than 0.06 was obtained as the smallest value of the results. This method was proved to be more convenient, less expensive and simpler than the HPLC method. No pretreatment of sample was required. The analytical results obtained provides guides for the synthesis of the objective product and also for its further industrial production.