Volume 48, Issue 7 e70056
Research Article

Resolution of Double Salts via Crystallization-Induced Diastereomeric Transformation (CIDT)

Melba Simon

Corresponding Author

Melba Simon

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

E-mail: [email protected]

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Sophie Shortt

Sophie Shortt

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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Conor Burke

Conor Burke

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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Eóin Bourke

Eóin Bourke

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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Anita Umerska

Anita Umerska

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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Angel Jacob

Angel Jacob

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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Sharon Davin

Sharon Davin

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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Brian Glennon

Brian Glennon

APC Ltd., Building 11, Cherrywood Business Park, Dublin, D18 DH50 Ireland

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First published: 09 June 2025

Abstract

The efficient enantioseparation of racemic compounds remains a critical challenge in pharmaceutical manufacturing. This investigation examines the crystallization-induced diastereomeric transformation (CIDT) of (S)-ketoprofen-(S)-phenylethylamine salts as a strategy for obtaining high-purity diastereomeric salts. Solubility phase diagrams were constructed for diastereomeric salts. A double salt system was identified, and a solvent system of 2-propanol and heptane (50:50 wt.%) was optimal for crystallization. Among the seven base catalysts screened, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) was found to be the most effective. Optimization studies demonstrated that 5–10 mol% DBU provides the highest purity (98.8 %) with 26.2 % yield. These results provide insights into the dual role of DBU as a catalyst (forming mixed salts) and cosolvent, influencing yield. The findings highlight CIDT as a robust method for the enantioseparation of diastereomeric salts in pharmaceutical applications.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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