title: An Examination of the Phase Transition Thermodynamics of (S)- and (RS)-Naproxen as a Basis for the Design of Enantioselective Crystallization Processes.
abstract: A detailed experimental analysis of the phase transition thermodynamics of (S)-naproxen and (RS)-naproxen is reported. Vapor pressures were determined experimentally via the transpiration method. Sublimation enthalpies were obtained from the vapor pressures and from independent TGA measurements. Thermodynamics of fusion which have been well-studied in the literature were systematically remeasured by DSC. Both sublimation and fusion enthalpies were adjusted to one reference temperature, T = 298 K, using measured heat capacities of the solid and the melt phase by DSC. Average values from the measurements and from literature data were suggested for the sublimation and fusion enthalpies. In order to prove consistency of the proposed values the vaporization enthalpies obtained by combination of both were compared to vaporization enthalpies obtained by the group-additivity method and the correlation-gas chromatography method. The importance of reliable and precise phase transition data for thermochemical calculations such as the prediction of solid/liquid phase behaviour of chiral compounds is highlighted.
authors.affiliation: Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Saxony-Anhalt, Germany. Electronic address: buchholz@mpi-magdeburg.mpg.de.
authors.forename: Hannes
authors.initials: H
authors.lastname: Buchholz
authors.affiliation: Department of Physical Chemistry, Kazan Federal University, Kazan, Tatarstan, Russia.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Emel'yanenko
authors.affiliation: Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Saxony-Anhalt, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Lorenz
authors.affiliation: Department of Physical Chemistry, Kazan Federal University, Kazan, Tatarstan, Russia; Department of Physical Chemistry and Department "Science and Technology of Life, Light and Matter," University of Rostock, Rostock, Mecklenburg-Vorpommern, Germany.
authors.forename: Sergey P
authors.initials: SP
authors.lastname: Verevkin
mesh_terms: D003460:Crystallization / Q000379:methods; D015195:Drug Design; D009288:Naproxen / Q000737:chemistry* / Q000378:metabolism; D044367:Phase Transition; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D009288:Naproxen
keywords: calorimetry; chirality; crystallization; phase transition; thermodynamics