Cellulose derivatives bearing pyrene-based π-conjugated pendants with circularly polarized luminescence in molecularly dispersed state
Cellulose derivatives bearing pyrene-based π-conjugated pendants with circularly polarized luminescence in molecularly dispersed state
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DOI：
10.1016/j.polymer.2017.04.032
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发表时间：
2017-05-19
期刊：
影响因子：
4.6
通讯作者：
Kanoh, Shigeyoshi
中科院分区：
文献类型：
--
作者：
Ikai, Tomoyuki;Kojima, Yutaka;Kanoh, Shigeyoshi
以微晶纤维素为原料，通过氨甲酰化和Sonogashira-Hagihara交叉偶联反应，合成了一系列以芘为基团的pi共轭悬浮体为荧光基团的新型纤维素衍生物，并研究了它们在溶液中的光致发光和圆偏振发光性质。纤维素衍生物Ce-1和Ce-2分别在重复葡萄糖单元的2，3，6-和2，3-位携带了芘单元，表现出绿色的CPL，不对称因子(GLUM)大于3.0×10-3。相反，类似的聚合物(Ce-3)和模型分子(Gl-1和Gl-2)主要发射蓝色单体荧光，其较低的GLU值小于0.5×10(-3)。从纤维主链衍生的螺旋手性和分子内分子内激基缔合物的形成被认为在高效的CPL中起着关键作用。(C)2017爱思唯尔有限公司。保留所有权利。
A series of novel cellulose derivatives bearing pyrene-based pi-conjugated pendants as a fluorescent unit was synthesized from microcrystalline cellulose via carbamoylation followed by Sonogashira-Hagihara cross-coupling, and their photoluminescence and circularly polarized luminescence (CPL) properties were investigated in solution. The cellulose derivatives Ce-1 and Ce-2 carrying the pyrene units at the 2,3,6- and 2,3-positions of the repeating glucose unit, respectively, exhibited greenish CPL with dissymmetry factors (glum) greater than 3.0 x 10-3. In contrast, the analogous polymer (Ce-3), carrying the pyrene unit only at the 6-position, and the model molecules (Gl-1 and Gl-2) mainly emitted bluish monomer fluorescence with lower glum values less than 0.5 x 10(-3). Both the helical chirality derived from the cellulose backbone and the intramolecular excimer formation of the pyrene units were considered to play key roles in the efficient CPL. (C) 2017 Elsevier Ltd. All rights reserved.