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Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature
Published on: December 20, 2016
Protic pharmaceutical ionic liquids and solids: aspects of protonics
Jelena Stoimenovski1, Pamela M Dean, Ekaterina I Izgorodina
1School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia.
Faraday Discussions
|March 30, 2012
Summary
New protic compounds, including ionic liquids, were synthesized. Their properties are determined by protonic behavior and hydrogen bonding, influencing ion association and potential in vivo membrane transport.
Area of Science:
- Chemical Synthesis
- Materials Science
- Physical Chemistry
Background:
- Active pharmaceutical ingredients (APIs) can be modified to create novel compounds with unique properties.
- Protic compounds, characterized by their ability to donate protons, exhibit diverse behaviors influencing their physical and chemical characteristics.
- Ionic liquids (ILs) are salts that exist in a liquid state below 100°C and possess tunable properties.
Purpose of the Study:
- To synthesize and characterize new protic compounds derived from APIs.
- To investigate the relationship between protonic behavior, molecular structure, and resulting properties (e.g., ionic liquid formation, melting point).
- To elucidate the extent of proton transfer and ion association in synthesized compounds, particularly ILs.
Main Methods:
- Synthesis and characterization of novel protic compounds.
- Indicator studies to assess proton transfer.
- Fourier-transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy.
- Transport property analysis using Walden plots.
- Crystal structure determination for related compounds.
Main Results:
- Successful synthesis and characterization of new protic compounds, some forming ionic liquids.
- Protonic behavior identified as a key determinant of compound properties.
- Walden plot analysis indicated significant ion association in primary amine-based compounds, attributed to hydrogen bonding.
- Crystal structures revealed the formation of extended hydrogen-bonded clusters in related salts.
Conclusions:
- The protonic nature of synthesized compounds significantly influences their properties, including ionic liquid formation and ion association.
- Strong ion association, driven by hydrogen bonding and resulting in cluster formation, was observed in primary amine-based salts.
- These hydrogen-bonded clusters may play a crucial role in determining the in vivo membrane transport properties of these compounds.
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