title: Chiroptical spectra of tetrakis (+)-3-heptafluorobutylrylcamphorate Ln(III) complexes with an encapsulated alkali metal ion: solution structures as revealed by chiroptical spectra.
abstract: The preparation of tetrakis((+)-hfbc) lanthanide(III) complexes with an encapsulated alkali metal and ammonium ions M[Ln((+)-hfbc)(4)] (hereafter abbreviated as M-Ln : (+)-hfbc, (+)-heptafluorobutyrylcamphorate; M, ammonium or benzyl ammonium ions as well as alkali metal ions) was reported and discussed. The electronic circular dichroism (CD) spectra in the intraligand π-π* transition of M-Ln were examined in view of the solvent effect. Here, the concentration, alkali metal, and ammonium ion dependences are compared with the solid CD, (5)D(0)←(7)F(0) (Eu(III)) excitation spectra, circularly polarized luminescence, and vibrational circular dichroism. It has been revealed that the dodecahedral eight coordinate DD-8-M-Ln complexes in crystals are equilibrated between the diastereoselectively formed square antiprism eight coordinate SAPR-8-M-Ln and [Ln((+)-hfbc)(3)] in EtOH and CH(3) CN solutions or between the SAPR-8-M-Ln and DD-D(2d) (mmmm)-8-M-Ln complexes in CHCl(3) solution. The observed CD couplets are found to reflect the exciton CD couplets which are useful to determine the four-bladed SAPR-(llll) absolute configuration around the lanthanide(III) ion.
authors.affiliation: Institute for Higher Education Research and Practice, Osaka University, Toyonaka, Japan.
authors.forename: Dai
authors.initials: D
authors.lastname: Shirotani
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Yamanari
authors.forename: Reiko
authors.initials: R
authors.lastname: Kuroda
authors.forename: Takunori
authors.initials: T
authors.lastname: Harada
authors.forename: Jamie L
authors.initials: JL
authors.lastname: Lunkley
authors.forename: Gilles
authors.initials: G
authors.lastname: Muller
authors.forename: Hisako
authors.initials: H
authors.lastname: Sato
authors.forename: Sumio
authors.initials: S
authors.lastname: Kaizaki
mesh_terms: D002164:Camphor / Q000737:chemistry*; D002942:Circular Dichroism; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008163:Luminescent Measurements; D008672:Metals, Alkali / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D055620:Optical Phenomena; D009942:Organometallic Compounds / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D028581:Lanthanoid Series Elements; D008672:Metals, Alkali; D009942:Organometallic Compounds; D000644:Quaternary Ammonium Compounds; D012996:Solutions; D012997:Solvents; D002164:Camphor