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Solution-phase racemization in the presence of an enantiopure solid phase
Cristobal Viedma1, Bastiaan J V Verkuijl, José E Ortiz
1Departamento Cristalografia-Mineralogia, Facultad Geologia, Universidad Complutense, 28040 Madrid, Spain. viedma@geo.ucm.es
Chemistry (Weinheim an Der Bergstrasse, Germany)
|April 2, 2010
Summary
Solid-phase deracemization is driven by solution-phase racemization via chiral amnesia. This study separates chemical and physical processes, confirming the Meyerhoffer double solubility rule under racemization conditions.
Area of Science:
- Chiral chemistry
- Crystallization processes
- Solid-state chemistry
Background:
- The Viedma "chiral amnesia" describes solid-phase deracemization driven by solution-phase racemization.
- Understanding the interplay between solution and solid phases is crucial for controlling chiral evolution.
Purpose of the Study:
- To elucidate the mechanism of solid-phase deracemization.
- To decouple chemical and physical rate processes in chiral systems.
- To validate the Meyerhoffer double solubility rule under racemization conditions.
Main Methods:
- Investigating the mechanism of solid-phase deracemization.
- Separating chemical (enantiomer interconversion) and physical (dissolution-reaccretion) processes.
- Analyzing enantiomer concentration profiles and racemization kinetics.
Main Results:
- Established a clearer understanding of solid-phase deracemization mechanisms.
- Differentiated solution-phase chemical rates from solid-phase physical transfer rates.
- Confirmed the Meyerhoffer double solubility rule for systems undergoing solution racemization.
Conclusions:
- Solution-phase racemization is the key driver for solid-phase chiral evolution.
- The study provides a mechanistic basis for controlling enantiomeric excess through solid-phase processes.
- The Meyerhoffer double solubility rule is robust under conditions of solution racemization.
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