Peculiar Concentration Dependence of H/D Exchange Reaction in 1-Butyl-3-methylimidazolium Tetrafluoroborate-D₂O Mixtures

Hiroshi Abe, Naohiro Hatano, Yusuke Ima, Souichi Ohta, Akio Shimizu, Yukihiro Yoshimura

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DOI: 10.4236/ojpc.2011.13010                

Abstract

We have investigated the H/D exchange reaction between heavy water and an ionic liquid, 1-butyl-3-methyl-imidazolium tetrafluoroborate ([bmim][BF4]), throughout the whole concentration region as a function of D₂O mol% at room temperature. We expected that the extent of the H/D reaction would increase linearly with increasing content of D₂O, but the results show an extended N-shaped behavior having a small maximum at around 40 mol% and the reaction becomes very slow at a specific concentration around 80 mol%. We found that this non-linear concentration dependence correlates with the pD dependence of the solutions.

Keywords

H/D Exchange Reaction, pD, NMR, Ionic Liquid

Conflicts of Interest

The authors declare no conflicts of interest.

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