Block modification of rod-shaped π conjugated carbon frameworks with donor and acceptor groups toward highly fluorescent molecules: synthesis and emission characteristics
Rod-shaped Oligophenyleneethynylenes Modified by Donor and Acceptor Groups in a Block Manner: Synthesis and Light-emitting Characteristics
作者:Takanori Ochi、Yoshihiro Yamaguchi、Shigeya Kobayashi、Tateaki Wakamiya、Yoshio Matsubara、Zen-ichi Yoshida
DOI:10.1246/cl.2007.794
日期:2007.6.5
Highly efficient blue light emmitters represented by BL-5 (Φ f = 0.96, λ em = 455nm in CHCl 3 ) and BL-8 (Φ f = 0.98, λ em = 464nm in CHCl 3 ) are created by block modification of oligophenylene ethynylenes with donor and acceptor groups. A linear relationship with positive slope between Φ f and the movability of the energetically equivalent dipolar structure unit is found for the first time.
以 BL-5 (Φ f = 0.96, λ em = 455nm in CHCl 3 ) 和 BL-8 (Φ f = 0.98, λ em = 464nm in CHCl 3 ) 为代表的高效蓝光发射器是通过低聚亚苯基乙炔的嵌段改性产生的与供体和受体组。首次发现Φ f 与能量等效偶极结构单元的可动性之间存在正斜率的线性关系。
Block modification of rod-shaped π conjugated carbon frameworks with donor and acceptor groups toward highly fluorescent molecules: synthesis and emission characteristics
作者:Takanori Ochi、Yoshihiro Yamaguchi、Tateaki Wakamiya、Yoshio Matsubara、Zen-ichi Yoshida
DOI:10.1039/b717832h
日期:——
To create organic molecules that are highly fluorescent at a longer wavelength region, we investigated the synthesis (using Pd-catalyzed cross-coupling) and photophysical properties (Φf, λem, Ï, λabs, and ε) of the following Ï conjugated molecular rods consisting of p-phenyleneethynylene units modified by donor (OMe) and/or acceptor (CN) groups: (1) side-donor modification systems (SD systems), (2) side-acceptor modification systems (SA systems), and (3) systems consisting of a donor block and an acceptor block (BL systems). As a consequence, very high Φf values (>0.95) were obtained for BL systems. Bathochromic shifts of λem for the same Ï conjugation length were largest for BL systems. Thus we succeeded in creating highly efficient light emitters at a longer wavelength region by block modification (e.g., Φf = 0.97, λem = 464 nm for BL-9). Considerably intense solid emission (Φf â¼ 0.5) at a longer wavelength region (500â560 nm) was also found for BL systems. It has been found that BL-6 and BL-8 exhibit interesting two photon absorption characteristics.