NMR Studies of Drugs. Enantiomeric Excess Determination of N-acetylcathinone with Eu(HFC)₃

Abstract

A technique for determination of enantiomeric excess of cathinone, 2-amino-1-phenyl-1-propanone, by use of the chiral lanthanide shift reagent (LSR), tris[3-(heptafluoropropylhydroxymethylene)-d-camphorato]europium (III), Eu (HFC)₃, is described. The hydrochloride salt of the cathinone sample is first converted directly to the N-acetyl derivative without need for isolation of the potentially unstable cathinone free base. Addition of Eu (HFC)₃ to the crude acetylated cathinone resulted in near-baseline resolution of the CH ₃CO resonances of the enantiomers. Analytical utility and the sense of magnetic nonequivalence of this signal were demonstrated using “spiked” non-racemic samples.

Key Words:

• Cathinone
• Khat (qat)
• Optical Purity
• Chiral Lanthanide Shift Reagent
• LSR
• Europium
• α-Aminopropiophenone
• Stereoisomer
• NMR Shift reagent
• Analysis