title: Application of L-proline derivatives as chiral shift reagents for enantiomeric recognition of carboxylic acids.
abstract: Four proline-derived chiral receptors 5-8 were readily synthesized starting from L-proline. The enantiomeric recognition ability of chiral receptors was examined with a series of carboxylic acids by (1) H NMR spectroscopy. The molar ratio and the association constants of the chiral compounds with each of the enantiomers of guest molecules were determined by using Job plots and a nonlinear least-squares fitting method, respectively. The Job plots indicate that the hosts form 1:1 instantaneous complexes with all guests. The receptors exhibited different chiral recognition abilities toward the enantiomers of racemic guests. Among the chiral receptors used in this study, prolinamide 6 was found to be the best chiral shift reagent and is effective for the determination of the enantiomeric excess of chiral carboxylic acids.
authors.affiliation: Department of Chemistry, Karamanoglu Mehmetbey University, Karaman, Turkey.
authors.forename: Hayriye Nevin
authors.initials: HN
authors.lastname: Naziroglu
authors.forename: Mustafa
authors.initials: M
authors.lastname: Durmaz
authors.forename: Selahattin
authors.initials: S
authors.lastname: Bozkurt
authors.forename: Abdulkadir
authors.initials: A
authors.lastname: Sirit
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry; D002264:Carboxylic Acids / Q000032:analysis* / Q000737:chemistry; D007202:Indicators and Reagents / Q000737:chemistry; D016018:Least-Squares Analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015394:Molecular Structure; D017711:Nonlinear Dynamics; D011392:Proline / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D002264:Carboxylic Acids; D007202:Indicators and Reagents; C010530:N-acetylalanine; D011392:Proline; D000409:Alanine; C056291:prolinamide