Roger Bouaziz

Optical resolution of (±)-N-acylnorfenfluramine derivatives by preferential crystallization

Abstract Three stable and one unstable conglomerates (i. e. eutectic mixtures of D and L crystals) were found among nine synthesized (±)-N-acylnorfenfluramine derivatives. Optical resolution of the stable conglomerates could be achieved by preferential crystallization method only under nonisothermal conditions.

Le polymorphisme du sulfate de sodium anhydre et les phases intermédiaires, glasérite et aphtitalite, dans le binaire Na2SO4-K2SO4

Abstract During studies on the evaluation of the by-products, the phase diagram of the binary system Na 2 SO 4 -K 2 SO 4 was reinvestigated. While the dimorphism of the potassium salt is obvious, the polymorphism of Na 2 SO 4 is subject to discussion: the compound NaK 3 (SO 4 ) 2 , glaserite, forms a large solid solution, and the mineral NaKSO 4 , aphtitalite, does not appear in the equilibrium diagram. In this study, these two compounds appear with stoichiometric compositions. Glaserite gives a peritectoic reaction at 444°C; aphtitalite has a congruent transformation at 470°C. At high temperatures, the hexagonal modifications of Na 2 SO 4 (form I) and K 2 SO 4 (α-form) show total miscibility.

Les chlorhydrates de la (S) et (RS) fenfluramine. Stabilites des énantiomeres et du racemate en milieu fondu et aqueux

Abstract ( s )-Fenfluramine hydrochloride (dextro-rotatory) C 12 H 17 ClF 13 N crystallizes from aqueous solutions and gives three polymorphic anhydrous forms: monoclinic P 21 , monoclinic C 2 and orthorhombic P 2 1 2 1 2 1 . The binary system water-( S )-fenfluramine hydrochloride defines the conditions of crystallization of each form. The binary diagram between the two enantiomers and few isotherms of the ternary system water-enantiomer-( S )-enantiomer-( R ) corroborate the existence of a large field of crystallization in a melt medium and in aqueous solutions for the racemic compound.