title: Development of separation methods for the chiral resolution of hexahelicenes.
abstract: In this short communication we report optimized procedures for the chiral separation of non-charged [6]helicene (1) and cationic derivative 1-butyl-3-(2-methyl[6]helicenyl)-imidazolium bromide (2) using high-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC) methods. The possibility of using capillary electrophoresis (CE) was also tested. The satisfactory results were obtained with SFC, where the highly selective resolution of four enantiopure 1 and 2 helicenes was achieved in a single run within 5min. The semi-preparative procedure for the isolation of P and M enantiomers of compound 2, including circular dichroism data, is reported here for the first time. The results could be used in further separations and analytical applications targeting carbohelicenes vs. positively charged helicene derivatives.
authors.affiliation: Institute of Chemical Process Fundamentals of the AS CR, v.v.i., Rozvojová 135, Prague 6, 165 02, Czechia.
authors.forename: Jan
authors.initials: J
authors.lastname: Storch
authors.affiliation: Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, Prague 2, 128 43, Czechia.
authors.forename: Květa
authors.initials: K
authors.lastname: Kalíková
authors.affiliation: Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, Prague 2, 128 43, Czechia.
authors.forename: Eva
authors.initials: E
authors.lastname: Tesařová
authors.affiliation: Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Faculty of Science, Palacký University, 17. listopadu 12, Olomouc, 771 46, Czechia.
authors.forename: Vítězslav
authors.initials: V
authors.lastname: Maier
authors.affiliation: Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc, 775 15, Czechia. Electronic address: jan.vacek@upol.cz.
authors.forename: Jan
authors.initials: J
authors.lastname: Vacek
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D011083:Polycyclic Compounds / Q000737:chemistry / Q000302:isolation & purification*; D013237:Stereoisomerism
chemical_list: D011083:Polycyclic Compounds; C031660:helicenes
keywords: Capillary electrophoresis; Chirality; Helicene; High-performance liquid chromatography; P/M enantiomer; Supercritical fluid chromatography