Chemical Papers

, Volume 68, Issue 2, pp 164–169 | Cite as

Synthesis of ethyl-6-aminohexanoate from caprolactam and ethanol in near-critical water

  • Zhi Qiang Hou
  • Li Gang Luo
  • Chun Ze Liu
  • Yuan Yuan WangEmail author
  • Li Yi DaiEmail author
Original Paper


The reaction between caprolactam and ethanol was performed in near-critical water. The primary product (ethyl-6-aminohexanoate) was identified by GC-MS. The influences of the reaction temperature, residence time, initial ratio (reactant/water), pH, and additives on the yields of ethyl-6-aminohexanoate are discussed. The results showed that the yield of ethyl-6-aminohexanoate could be as high as 98 % with SnCl2 as an additive in near-critical water. At the same time, the reaction between caprolactam and ethanol was estimated by a lumped kinetic equation as a second-order reaction in near-critical water, and the activation energy was evaluated according to the Arrhenius equation under acidic and basic conditions. Based on the results, the reaction mechanism between caprolactam and ethanol in near-critical water is proposed.


near-critical water caprolactam ethanol ethyl-6-aminohexanoate kinetics mechanism 


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Copyright information

© Institute of Chemistry, Slovak Academy of Sciences 2013

Authors and Affiliations

  1. 1.Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of ChemistryEast China Normal UniversityShanghaiChina

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