title: Tricyclic Quaternary Ammonium Salts Derived from Cinchona Alkaloids.
abstract: Tricyclic systems with quaternary bridgehead nitrogen atoms are rare but an interesting class of compounds. Chiral quinuclidine derivative salts with fused five and six-membered rings (X-ray) were obtained via modification of Cinchona alkaloids. The ease of ring formation was dependent on its size, while even mild activation sufficed to close the five membered ring. On the other hand the systems with fused benzene and a six-membered ring formed atropisomers separated by a barrier of ca. 15 kcal/mol, whose interconversion was studied by DFT and NMR.
authors.affiliation: Department of Organic Chemistry, Wrocław University of Technology , 50-370 Wrocław, Poland.
authors.forename: Przemysław J
authors.initials: PJ
authors.lastname: Boratyński
authors.affiliation: Department of Organic Chemistry, Wrocław University of Technology , 50-370 Wrocław, Poland.
authors.forename: Rafał
authors.initials: R
authors.lastname: Kowalczyk
authors.affiliation: Department of Organic Chemistry, Wrocław University of Technology , 50-370 Wrocław, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Kobylańska
authors.affiliation: Advanced Materials Engineering and Modelling Group, Wrocław University of Technology , 50-370 Wrocław, Poland.
authors.forename: Julia
authors.initials: J
authors.lastname: Bąkowicz
mesh_terms: D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002930:Cinchona Alkaloids / Q000737:chemistry*; D015394:Molecular Structure; D066244:Proton Magnetic Resonance Spectroscopy; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013816:Thermodynamics
chemical_list: D002930:Cinchona Alkaloids; D000644:Quaternary Ammonium Compounds; D012492:Salts