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Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis

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Role of Additives during Deracemization Using Temperature Cycling.

Giuseppe Belletti¹, Hugo Meekes¹, Floris P J T Rutjes¹

¹Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 ED Nijmegen, The Netherlands.

Crystal Growth & Design

|November 20, 2018

Summary

Chiral additives accelerate temperature cycling for deracemizing chiral compounds. The additive

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Area of Science:

Chiral chemistry
Crystallization science

Background:

Temperature cycling combined with Viedma ripening is a known method for deracemizing racemic mixtures of chiral compounds that crystallize as conglomerates.
Viedma ripening alone is a slower process for achieving deracemization.

Purpose of the Study:

To investigate the effect of chiral additives on the speed of temperature cycling for deracemization.
To determine if the chirality of the additive influences the enantiomeric outcome of the solid phase.

Main Methods:

Utilizing temperature cycling in conjunction with Viedma ripening.
Introducing chiral additives to the racemic mixtures during the process.
Comparing the speed and enantiomeric outcome with and without chiral additives.

Main Results:

The speed of temperature cycling was significantly increased by the addition of chiral additives.
The enantiomeric state of the final solid phase was dictated by the chirality of the additive used.
Viedma ripening experiments were consistently slower when chiral additives were absent.

Conclusions:

Chiral additives can enhance the efficiency of temperature cycling for deracemizing conglomerate-forming chiral compounds.
The use of chiral additives offers control over the enantiomeric outcome of the deracemization process.