The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Qichun Zhang - One of the best experts on this subject based on the ideXlab platform.

Chengyuan Wang - One of the best experts on this subject based on the ideXlab platform.

Timothy Noel - One of the best experts on this subject based on the ideXlab platform.

Li Qiu - One of the best experts on this subject based on the ideXlab platform.

  • reductive ring closure methodology toward Heteroacenes bearing a dihydropyrrolo 3 2 b pyrrole core scope and limitation
    ChemInform, 2015
    Co-Authors: Li Qiu, Na Zhao, Xiao Wang, Xuhui Zhuang, Zhenggang Lan, Lirong Wen, Xiaobo Wan
    Abstract:

    A newly developed reductive ring closure methodology to Heteroacenes bearing a dihydropyrrolo[3,2-b]pyrrole core was systematically studied for its scope and limitation. The methodology involves (i) the cyclization of an o-aminobenzoic acid ester derivative to give an eight-membered cyclic dilactam, and (ii) the conversion of the dilactams into the corresponding diimidoyl chloride, which undergoes (iii) reductive ring closure to install the dihydropyrrolo[3,2-b]pyrrole core. The first step of the methodology plays the key role due to its substrate limitation, which suffers from the competition of oligomerization and hydrolysis. All the dilactams could successfully convert to the corresponding diimidoyl chlorides, most of which succeeded to give the dihydropyrrolo[3,2-b]pyrrole core. The influence of the substituents and the elongation of conjugated length on the photophysical properties of the obtained Heteroacenes were then investigated systematically using UV-vis spectroscopy and cyclic voltammetry. It was found that chlorination and fluorination had quite a different effect on the photophysical properties of the Heteroacene, and the ring fusing pattern also had a drastic influence on the band gap of the Heteroacene. The successful preparation of a series of Heteroacenes bearing a dihydropyrrolo[3,2-b]pyrrole core would provide a wide variety of candidates for further fabrication of organic field-effect transistor devices.

  • Antiaromatic Characteristic Analysis of 1,4-Diazapentalene Derivatives: A Theoretical Study
    2015
    Co-Authors: Zheng Jie, Li Qiu, Zhuang Xuhui, Yu Xie, Wan Xiaobo, Lan Zhenggang
    Abstract:

    1,4-Diazapentalene Heteroacenes are potential n-type semiconductors that could be used as a new type of material for organic field-effect transistors (OFETs), but their synthesis is still challenging due to their antiaromaticity. The study on their structure-stability relationship should provide useful guidance to the design of stable diazapentalenes. We examined the stability of several types of Heteroacenes hearing the 1,4-diazapentalene core using NICS(1)(zz) calculations. The influence of the fusion pattern, the introduction of substituents, and the incorporation of other heterocycles on the antiaromaticity of the central 1,4-diazapentalene core was systematically studied. It was found that the linear fusion of aromatic rings to the antiaromatic core increases the stability of the Heteroacene. The fusion of electron-poor heterocyclic rings also enhances the stability effectively, Whereas the fusion of electron-rich heterocyclic rings destabilizes the system. In addition, the combination of the linear fusion pattern or introduction of electron-poor heterocyclic rings to the antiaromatic core reduces the reorganization energy for electron transport, suggesting a way to achieve better n-type semiconductors

  • Antiaromatic Characteristic Analysis of 1,4-Diazapentalene Derivatives: A Theoretical Study
    2015
    Co-Authors: Jie Zheng, Xiaobo Wan, Li Qiu, Xuhui Zhuang, Yu Xie, Zhenggang Lan
    Abstract:

    1,4-Diazapentalene Heteroacenes are potential n-type semiconductors that could be used as a new type of material for organic field-effect transistors (OFETs), but their synthesis is still challenging due to their antiaromaticity. The study on their structure–stability relationship should provide useful guidance to the design of stable diazapentalenes. We examined the stability of several types of Heteroacenes bearing the 1,4-diazapentalene core using NICS(1)zz calculations. The influence of the fusion pattern, the introduction of substituents, and the incorporation of other heterocycles on the antiaromaticity of the central 1,4-diazapentalene core was systematically studied. It was found that the linear fusion of aromatic rings to the antiaromatic core increases the stability of the Heteroacene. The fusion of electron-poor heterocyclic rings also enhances the stability effectively, whereas the fusion of electron-rich heterocyclic rings destabilizes the system. In addition, the combination of the linear fusion pattern or introduction of electron-poor heterocyclic rings to the antiaromatic core reduces the reorganization energy for electron transport, suggesting a way to achieve better n-type semiconductors

  • Reductive Ring Closure Methodology toward Heteroacenes Bearing a Dihydropyrrolo[3,2‑b]pyrrole Core: Scope and Limitation
    2014
    Co-Authors: Li Qiu, Na Zhao, Xiao Wang, Xuhui Zhuang, Zhenggang Lan, Lirong Wen, Xiaobo Wan
    Abstract:

    A newly developed reductive ring closure methodology to Heteroacenes bearing a dihydropyrrolo­[3,2-b]­pyrrole core was systematically studied for its scope and limitation. The methodology involves (i) the cyclization of an o-aminobenzoic acid ester derivative to give an eight-membered cyclic dilactam, and (ii) the conversion of the dilactams into the corresponding diimidoyl chloride, which undergoes (iii) reductive ring closure to install the dihydropyrrolo­[3,2-b]­pyrrole core. The first step of the methodology plays the key role due to its substrate limitation, which suffers from the competition of oligomerization and hydrolysis. All the dilactams could successfully convert to the corresponding diimidoyl chlorides, most of which succeeded to give the dihydropyrrolo­[3,2-b]­pyrrole core. The influence of the substituents and the elongation of conjugated length on the photophysical properties of the obtained Heteroacenes were then investigated systematically using UV–vis spectroscopy and cyclic voltammetry. It was found that chlorination and fluorination had quite a different effect on the photophysical properties of the Heteroacene, and the ring fusing pattern also had a drastic influence on the band gap of the Heteroacene. The successful preparation of a series of Heteroacenes bearing a dihydropyrrolo­[3,2-b]­pyrrole core would provide a wide variety of candidates for further fabrication of organic field-effect transistor devices

  • An expedient synthesis of fused Heteroacenes bearing a pyrrolo[3,2-b]pyrrole core
    Chemical Communications, 2012
    Co-Authors: Li Qiu, Chunmeng Yu, Xiaobo Wan, Renqiang Yang, Weichao Chen, Yunlong Guo, Na Zhao, Yunqi Liu
    Abstract:

    Two linear fused Heteroacenes bearing a pyrrolo[3,2-b]pyrrole core have been synthesized via a novel reductive ring closure methodology in three steps and in good overall yield. Preliminary OFET results showed that dinaphtho[2,3-b:2',3'-f]pyrrolo[3,2-b]pyrrole (DNPP) is a potential candidate for organic electronics.

Yunqi Liu - One of the best experts on this subject based on the ideXlab platform.