title: Chiral Recognition Studies of α-(Nonafluoro-tert-butoxy)carboxylic Acids by NMR Spectroscopy.
abstract: Three chiral α-(nonafluoro-tert-butoxy)carboxylic acids (R)-1, (RS)-2, (R)-3 were synthesized to examine their application as chiral solvating agents with amines. As a model compound, first (S)- and/or (RS)-α-phenylethylamine was used, and their diastereomeric salts were investigated by (1)H and (19)F NMR and ECD spectroscopy. The NMR spectroscopic studies were carried out at room temperature using the slightly polar CDCl3 and apolar C6D6 as solvents in 5 mM and 54 mM concentrations. The difference of the chemical shifts (Δδ) in the diastereomeric complexes is comparable with other, well-known chiral derivatizing and solvating agents (e.g., Mosher's acid, Pirkle's alcohol). Diastereomeric salts of racemic acids (RS)-1 and (RS)-2 with biologically active amines (1R,2S)-ephedrine and (S)-dapoxetine were also investigated by (19)F NMR spectroscopy.
authors.affiliation: †Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
authors.forename: Anikó
authors.initials: A
authors.lastname: Nemes
authors.affiliation: †Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
authors.forename: Tamás
authors.initials: T
authors.lastname: Csóka
authors.affiliation: ‡Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes Endre utca 9, 1092 Budapest, Hungary.|§Department of Pharmacognosy, Semmelweis University, Üllői út 26, 1085, Budapest, Hungary.
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Béni
authors.affiliation: ⊥MTA-ELTE Protein Modelling Research Group, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
authors.forename: Viktor
authors.initials: V
authors.lastname: Farkas
authors.affiliation: †Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
authors.forename: József
authors.initials: J
authors.lastname: Rábai
authors.affiliation: †Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
authors.forename: Dénes
authors.initials: D
authors.lastname: Szabó
mesh_terms: D001596:Benzylamines / Q000737:chemistry; D002264:Carboxylic Acids / Q000737:chemistry; D004809:Ephedrine / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009281:Naphthalenes / Q000737:chemistry; D010627:Phenethylamines / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D001596:Benzylamines; D002264:Carboxylic Acids; D006845:Hydrocarbons, Fluorinated; D009281:Naphthalenes; D010627:Phenethylamines; D012997:Solvents; C080598:dapoxetine; D004809:Ephedrine; C033198:1-phenethylamine