Preferential Enrichment of DL-Leucine Using Cocrystal Formation With Oxalic Acid Under Nonequilibrium Crystallization Conditions

Kochunnoonny Manoj; Hiroki Takahashi; Yoko Morita; Rajesh G Gonnade; Sekai Iwama; Hirohito Tsue; Rui Tamura

doi:10.1002/chir.22431

Preferential Enrichment of DL-Leucine Using Cocrystal Formation With Oxalic Acid Under Nonequilibrium Crystallization Conditions

Chirality. 2015 Jul;27(7):405-10. doi: 10.1002/chir.22431. Epub 2015 Feb 13.

Authors

Kochunnoonny Manoj¹, Hiroki Takahashi¹, Yoko Morita¹, Rajesh G Gonnade², Sekai Iwama³, Hirohito Tsue¹, Rui Tamura¹

Affiliations

¹ Graduate School of Human & Environmental Studies, Kyoto University, Kyoto, Japan.
² Centre for Materials Characterization, National Chemical Laboratory, CSIR-NCL, Pune, India.
³ Group of Chemistry, Faculty of Law, Meijigakuin Universiy, Yokohama, Japan.

PMID: 25683517
DOI: 10.1002/chir.22431

Abstract

By utilizing the preferential enrichment (PE) technique, we achieved an improved enantiomeric resolution of DL-leucine (Leu) using a 1:1 cocrystal (DL-) of DL-Leu and oxalic acid. The crystal structure analysis of DL- indicated the occurrence of a novel type of phase transition and subsequent preferential redissolution of one enantiomer from the resulting crystals into solution.

Keywords: chiral resolution; cocrystal formation; leucine; phase transition; preferential enrichment.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Crystallization / methods*
Crystallography, X-Ray
Leucine / chemistry*
Oxalic Acid / chemistry*
Stereoisomerism

Substances

Oxalic Acid
Leucine