Photoinduced Charge Separation Prompted Intervalence Charge Transfer in a Bis(thienyl)diketopyrrolopyrrole Bridged Donor‐TCBD Push‐Pull System
Photoinduced Charge Separation Prompted Intervalence Charge Transfer in a Bis(thienyl)diketopyrrolopyrrole Bridged Donor‐TCBD Push‐Pull System
复制标题
双（噻吩基）二酮吡咯并吡咯桥桥供体 - TCBD 推 - 拉系统中光致电荷分离促进间隔电荷转移
DOI：
10.1002/anie.202108293
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
D'Souza, Francis
中科院分区：
文献类型：
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作者：
Khan, Faizal;Jang, Youngwoo;Patil, Yuvraj;Misra, Rajneesh;D'Souza, Francis
在一种新合成的新型多模块供体-受体系统中报告了在由两个氧化态相差一个单元的氧化还原中心组成的分子系统中观察到的价间电荷转移（IVCT）现象，该系统由中心双（噻吩基）二酮吡咯并吡咯（TDPP）在相对侧托管两个吩噻嗪-四氰基丁二烯（PTZ-TCBD）实体组成。TCBD的单电子还原促进了两个TCBD之间的电子交换，导致近红外区域的IVCT转变。由分裂还原波的峰电位计算得到的稳定化能-Δ Gcom和歧化平衡常数Kcom分别为1.06× 104 J mol-1和72.3 M-1。 此外，IVCT转变也见证了在系统中的TDPP实体的激发后的物理上可行的电子转移的过程中，并作为一个诊断标志物，以表征电子转移产品。随后的瞬态吸收光谱研究和Global和Target分析的数据分析显示，由于多模块供体-受体系统实体之间的紧密接近和良好通信，发生了超快电荷分离（kcs <$1010s −1）。中央TDPP在促进IVCT的作用是从目前的调查证明。
Intervalence charge transfer (IVCT), a phenomenon observed in molecular systems comprised of two redox centers differing in oxidation states by one unit, is reported in a novel, newly synthesized, multi‐modular donor‐acceptor system comprised of central bis(thienyl)diketopyrrolopyrrole (TDPP) hosting two phenothiazine‐tetracyanobutadiene (PTZ‐TCBD) entities on the opposite sides. One‐electron reduction of TCBD promoted electron exchange between the two TCBD resulting in IVCT transition in the near‐infrared region. The stabilization energy, −ΔGcomand comproportionation equilibrium constant,Kcomcalculated from peak potentials of the split reduction waves were found to be 1.06×104J mol−1, and 72.3 M−1, respectively. Further, the IVCT transition was also witnessed during the process of thermodynamically feasible electron transfer upon excitation of the TDPP entity in the system, and served as a diagnostic marker to characterize the electron transfer product. Subsequent transient absorption spectral studies and data analysis by Global and Target analyses revealed occurrence of ultrafast charge separation (kcs≈1010s−1) owing to the close proximity and good communication between the entities of the multi‐modular donor‐acceptor system. The role of central TDPP in promoting IVCT is borne out from the present investigation.