A donorâacceptorâdonor dyad 4 involving 2-sulfur-3-methylthio-6,7-bis(hexylthio)tetrathiafulvalene (TTF) as a donor attached directly to N,Nâ²-dibutylperylene-3,4,9,10-tetracarboxylic diimide (PDI) as an acceptor was synthesized by condensation of N,Nâ²-dibutyl-1,6-dibromo-3,4,9,10-perylenetetracarboxylic diimide and 2-(2-cyanoethylthio-3-methylthio-6,7-bis(hexylthio)tetrathiafulvalene. The cyclic voltammetric (CV) data implied significant intramolecular interaction and the absorption spectrum indicated that there was an intramolecular charge transfer (ICT) interaction between TTF and PDI moieties in dyad 4. Comparing with PDI 13, the fluorescence emission intensity of dyad 4 was quenched almost quantitatively, which might result from the photo-induced electron transfer (PET) interaction between the PDI and TTF moieties in dyad 4. The fluorescence intensity of dyad 4 could be reversibly modulated by sequential oxidation and reduction of the TTF unit using chemical methods. Thus dyad 4 can be regarded as a new reversible fluorescence-redox dependent molecular switch.
通过缩合 N,N²-二丁基-1,6-二
溴-3,4,9,10-四
羧酸二
亚胺(PDI)作为受体,合成了供体-受体-受体四元化合物、通过缩合 N,N²-二丁基-1,6-二
溴-3,4,9,10-过烯四
羧酸二
亚胺和 2-(2-
氰基乙
硫基-3-甲
硫基-6,7-双(己
硫基)四
硫代
富勒烯,合成了作为受体的 10-四
羧酸二
亚胺(PDI)。循环伏安(CV)数据表明存在显著的分子内相互作用,而吸收光谱则表明在对偶 4 中,
TTF 和 PDI 分子之间存在分子内电荷转移(ICT)相互作用。与 PDI 13 相比,
染料 4 的荧光发射强度几乎被定量淬灭,这可能是
染料 4 中 PDI 和
TTF 分子之间的光诱导电子转移(PET)作用所致。使用
化学方法依次氧化和还原
TTF 单元,可以可逆地调节
染料 4 的荧光强度。因此,共轭物 4 可被视为一种新的可逆荧光-氧化还原依赖性分子开关。