title: Optically active mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes. Synthesis, spectroscopy, and effective chiral information transfer.
abstract: With the view to creating novel sandwich-type tetrapyrrole rare earth complexes toward potential applications in material science and chiral catalysis, two new optically active mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes with both (R)- and (S)-enantiomers [M(2)(Pc)(2)(TCBP)] {TCBP = Meso-tetrakis [3,4-(11,12:13,14-di(1',2'-naphtho)-1,4,7,10,15,18-hexaoxacycloeicosa-2,11,13-triene)-phenyl] porphyrinate; M = Eu (1), Y (2)} have been designed and prepared by treating optically active metal free porphyrin (R)-/(S)-H(2)TCBP with M(Pc)(2) in the presence of corresponding M(acac)(3)·nH(2)O (acac = acetylacetonate) in refluxing 1,2,4-trichlorobenzene (TCB). These novel mixed ring rare earth triple-decker compounds were characterized by a wide range of spectroscopic methods including MS, (1)H NMR, IR, electronic absorption, and magnetic circular-dichroism (MCD) spectroscopic measurements in addition to elemental analysis. Perfect mirror image relationship was observed in the Soret and Q absorption regions in the circular-dichroism (CD) spectra of the (R)- and (S)-enantiomers, indicating the optically active nature of these two mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes. This result reveals the effective chiral information transfer from the peripheral chiral binaphthyl units to the porphyrin and phthalocyanine chromophores in the triple-decker molecule because of the intense π-π interaction between porphyrin and phthalocyanine rings. In addition, their electrochemical properties have also been investigated by cyclic voltammetry (CV).
authors.affiliation: Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
authors.forename: Jitao
authors.initials: J
authors.lastname: Lu
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Deng
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Zhang
authors.forename: Nagao
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Jianzhuang
authors.initials: J
authors.lastname: Jiang
mesh_terms: D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D007211:Indoles / Q000737:chemistry*; D054833:Isoindoles; D008674:Metals, Rare Earth / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry*
chemical_list: D007211:Indoles; D054833:Isoindoles; D008674:Metals, Rare Earth; D009942:Organometallic Compounds; D011166:Porphyrins; C013647:phthalocyanine