Chiral co-crystallization for enantiomer separation

Chiral co-crystallization for enantiomer separation

De Groen, M.

Horst, J.H. (mentor)

Mechanical, Maritime and Materials Engineering

Process and Energy

IRS

2010-05-25

Co-crystallization is a technique which can be applied for the separation of enantiomers. Usually, enantiomers do not form eutectic mixtures, which are easy to separate. The determination of the pure component solubility is one of the key steps in co-crystal screening: the region in the phase diagram in which the co-crystal is formed, depends on the solubility of the pure components. The UNIFAC model can be used for preliminary estimations of the solubility. RS-atenolol and DL-amino acids were used for co-crystal screening. RSatenolol forms a solid solution and DL-amino acids form a racemic compound or a conglomerate. RS-atenolol and L-malic acid (L-MA) form a salt, which is very stable in ethanol at low concentration of L-MA. Atenolol with dibenzoyl-L-tartaric acid forms two liquid phases in ethanol: a liquid and a viscous oil phase. No crystals could be obtained from this combination, even not at long storing at room temperature. Only hydrophobic amino acids formed co-crystals during cooling crystallization. Due to steric hindrance, only D-L combinations of amino acids can be co-crystallized, this leads to separation of enantiomers. Separations were performed for DL-Val with L-Phe and for DL-Phe with L-Phe and L-Leu.

co-crystallization

http://resolver.tudelft.nl/uuid:2dcf7bfb-5abb-4b48-a5cf-8e1eddcb1339

Student theses

master thesis

(c) 2010 De Groen, M.