Enantiomeric 3-chloromandelic acid system: binary melting point phase diagram, ternary solubility phase diagrams and polymorphism.
A systematic study of binary melting point and ternary solubility phase diagrams of the enantiomeric 3-chloromandelic acid (3-ClMA) system was performed under consideration of polymorphism. The melting point phase diagram was measured by means of thermal analysis, that is, using heat-flux differential scanning calorimetry (DSC). The results reveal that 3-ClMA belongs to the racemic compound-forming systems. Polymorphism was found for both the enantiomer and the racemate as confirmed by X-ray powder diffraction analysis. The ternary solubility phase diagram of 3-ClMA in water was determined between 5 and 50 degrees C by the classical isothermal technique. The solubilities of the pure enantiomers are extremely temperature-dependent. The solid-liquid equilibria of racemic 3-ClMA are not trivial due to the existence of polymorphism. The eutectic composition in the chiral system changes as a function of temperature. Further, solubility data in the alternative solvent toluene are also presented.
Le Minh
Tam
T
Max-Planck-Institut für Dynamik Komplexer Technischer Systeme, Magdeburg, Sachsen-Anhalt, Germany. le@mpi-magdeburg.mpg.de
von Langermann
Jan
J
Lorenz
Heike
H
Seidel-Morgenstern
Andreas
A
D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D005615:Freezing; D008333:Mandelic Acids / Q000737:chemistry*; D012995:Solubility; D013237:Stereoisomerism; D014961:X-Ray Diffraction
C553672:3-chloromandelic acid; D008333:Mandelic Acids