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Updated: May 17, 2026
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Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments
Published on: January 23, 2018
Interconversion between different stoichiometric forms of a three-component crystal via liquid-assisted grinding
Leigh Loots1, Helene Wahl, Leandi van der Westhuizen
1Department of Chemistry and Polymer Science, University of Stellenbosch, P. Bag X1, Matieland, 7602, Republic of South Africa.
Chemical Communications (Cambridge, England)
|October 10, 2012
Summary
A new polymorphic salt form was created using liquid-assisted grinding. This salt can be easily converted into another salt form by adjusting the amounts of pamoic acid or DABCO.
Area of Science:
- Crystallography
- Solid-state chemistry
Background:
- Polymorphism in salts can affect physicochemical properties.
- Controlling salt stoichiometry is crucial for pharmaceutical development.
Purpose of the Study:
- To investigate the formation and interconversion of polymorphic salt forms.
- To explore the use of liquid-assisted grinding for salt synthesis and modification.
Main Methods:
- Liquid-assisted grinding was employed to synthesize and interconvert salt forms.
- Stoichiometric control of pamoic acid and DABCO was utilized.
Main Results:
- A second polymorphic form of a 1:2:3 pamoate:DABCO:water salt was successfully obtained.
- Facile interconversion between 1:2:3 and 1:1:2 stoichiometric salts was demonstrated via liquid-assisted grinding.
Conclusions:
- Liquid-assisted grinding is an effective method for controlling salt stoichiometry and polymorphism.
- The facile interconversion highlights the dynamic nature of these salt systems.
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