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Research & Reviews: Journal of Material Sciences | ISSN: 2321-6212 | Volulme 6
November 07-08, 2018 | Atlanta, USA
Materials Science and Engineering
15
th
International Conference and Exhibition on
Applied Crystallography
3
rd
International Conference on
&
Strongly circularly polarized luminescence from dinuclear Eu(III) helicates prepared through a BINOL-
based bis-β-diketone ligands
Shuang Bi, Yanyan Zhou, Hongfeng Li, Peng Chen, Wenbin Sun, Ting Gao
and
Pengfei Yan
Heilongjiang University, China
C
hiral lanthanide helicates have potential applications in biology and material science as chiral probes and circularly polarized
luminescence (CPL) materials. However, the preparation of homochiral helicates through coordination-directed self-assembly
strategy is challenging due to the greatly labile coordination geometries of lanthanides, which raised the higher requirement for
ligand designs. Herein, a BINOL-based bis-β-diketone ligand is developed, which give rise to preorganized helical conformation and
induced the formation of homochiral helical structure. X-ray crystallographic analysis reveals that the ligand assemble with Ln(III)
ions to give homochiral either P or M quadruple- and triple-stranded helicates, [HNEt3]2+•[Eu
2
(BTTB)
4
]2- and Eu
2
(BTTB)3(R/
S-BINAPO)2 {(R/S)-BINAPO=(R/S)-2,2'-bis(diphenylphosphoryl)-1,1'-binaphthyl; BTTB=bis[4-(4,4,4-trifluoro-1,3-dioxobutyl)
(2,3,5,6-tetrafluorophenoxyl)]-1,1'-binaphthalene}. The
1
H,
31
P NMR and CD measurements confirm the diastereo purity of the
assemblies in solution. A detailed optical and chiroptical characterization reveals that the luminescent enantiopure helicates not only
exhibit intense circularly polarized luminescence (CPL) with |glum| values reaching 0.80 but also show high luminescence quantum
yields of 72.8%. Our results provide a feasible strategy for designing homochiral helical lanthanide supramolecular architecture and
synthesizing excellent CPL materials.
yanpf@vip.sina.comRes. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C8-036