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Crystallization, Dehydration, and Phase Transformations of Diastereomeric Salts: L ‐Ephedrine and D ‐Tartaric Acid
Author(s) -
Wu H.,
Jones A. G.
Publication year - 2012
Publication title -
chemical engineering and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.403
H-Index - 81
eISSN - 1521-4125
pISSN - 0930-7516
DOI - 10.1002/ceat.201100683
Subject(s) - tartrate , differential scanning calorimetry , tartaric acid , thermogravimetric analysis , crystallization , anhydrous , chemistry , dehydration , diastereomer , stoichiometry , nuclear chemistry , inorganic chemistry , organic chemistry , citric acid , biochemistry , physics , thermodynamics
A screening of crystallization conditions for the diastereomeric salts formed by L/D‐tartaric acid and a common chiral resolving agent, L‐ephedrine, in water is reported. Eight different salts with 1:1 and 2:1 stoichiometries were synthesized, identified, and characterized, including three previously reported LL‐salts. All new LD‐salts were investigated by differential scanning calorimetry, thermogravimetric and elemental analysis, infrared spectroscopy, solid‐state NMR, and powder XRD. 1:1 LD‐tartrate is anhydrous and 2:1 LD‐tartrate crystallizes as a monohydrate; its dehydration and phase transformations on heating were monitored in situ by variable‐temperature XRD and hot‐stage microscopy.