ABSTRACT

In this study, the binary and the ternary phase diagrams of R-/S-ketamine were determined based on differential scanning calorimetry (DSC) measurements. The binary phase diagram presented a eutectic point in the 50:50 (R/S) composition which characterizes the product as a conglomerate forming system. On the other hand, the ternary phase diagram in the presence of ethanol showed a eutectic point in the 75:25 (R/S) composition, indicating the occurrence of a racemic compound. The observed facts indicate that the solvent and the temperature may affect the eutectic point, and thus different crystal forming systems can be obtained from the melt and from the solution. The calorimetric method was demonstrated to be an excellent short-cut method for the fast construction of phase diagrams, taking only some hours and consuming only a few milligrams [(5 to 20) mg] of samples.

Compounds

#	Formula	Name
1	C13H16ClNO	(S)-ketamine
2	C13H16ClNO	(R)-ketamine
3	C2H6O	ethanol
4	C13H16ClNO	(.+-.)-2-(2-chlorophenyl)-2-(methylamino)cyclohexanone

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	1	Molar enthalpy of transition or fusion, kJ/mol ; Crystal			Crystal Liquid Gas	DSC	1
POMD	1	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal			Crystal Liquid Air at 1 atmosphere	DSC	1
POMD	2	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	1 2	Eutectic temperature, K ; Crystal - 2			Crystal - 2 Crystal - 1 Liquid Air at 1 atmosphere	DTA::	1
POMD	1 2	Solid-liquid equilibrium temperature, K ; Liquid	Mole fraction - 2; Liquid	Pressure, kPa; Liquid	Liquid Crystal - 2	DSC	8
POMD	3 4	Mass fraction - 4 ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid Crystal - 4	DSC	8

Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Determination of the Binary and Ternary Phase Diagrams of R(+)-/ S(-)-Ketamine Using Differential Scanning Calorimetry

Tamagawa, R. E.[Rosana Emi], Miranda, E. A.[Everson Alves], Santana, C. C.[Cesar Costapinto], Giulietti, M.[Marco]

ABSTRACT