Recognition in Chiral Ionic Liquids: The Achiral Cation Makes the Difference!

By simulating butan-2-ol dissolved in the chiral ionic liquid 1-ethyl-3methylimidazolium (S)-alaninate, we investigate the chiral recognition of butan-2-ol in the ionic liquid. The hydrogen bonding between the chiral anion and both enantiomers of butan-2-ol is similar; however, both chiral molecules (anion and alcohol) induce an asymmetry in the achiral cation which leads to a more favorable environment for the alcohol in the heterochiral system as compared to the homochiral system and hence provides an energetic stabilization of the former.

Automated summary

This study investigates the chiral recognition of butan-2-ol in a chiral ionic liquid, 1-ethyl-3-methylimidazolium (S)-alaninate, by simulating the system. The hydrogen bonding between the chiral anion and both enantiomers of butan-2-ol is found to be similar, but the chiral molecules induce an asymmetry in the achiral cation, creating a more favorable environment for the alcohol in the heterochiral system. This leads to an energetic stabilization of the alcohol in the heterochiral system compared to the homochiral system.