20138-79-8Relevant articles and documents
Two 3D Cd(II) Metal-Organic Frameworks Linked by Benzothiadiazole Dicarboxylates: Fantastic S@Cd6 Cage, Benzothiadiazole Antidimmer, and Dual Emission
Cheng, Qing,Han, Xiao,Tong, Yue,Huang, Chao,Ding, Jie,Hou, Hongwei
, p. 1696 - 1705 (2017)
On the basis of the same benzothiadiazole (BTD) ligand 2,1,3-benzothiadiazole-4,7-dicarboxylic acid (H2L), two new isomers of three-dimensional (3D) BTD-derived Cd(II) metal-organic frameworks 1-2 {[S@Cd6L6]·xH2O}n were obtained by the different solvothermal reactions, which were structurally similar. Surprisingly, structural analyses reveal that in 1 or 2, one free sulfur atom was fixed in a Cd(II) cluster cage by strong intermolecular interaction to form the secondary building unit (SBU) S@Cd6. Each SBU S@Cd6 is connected by six L2- ligands and further extended into the 3D porous framework. In this work, the BTD antidimmer was evidenced by structural analysis and photophysical study. Furthermore, either 1 or 2 showed the uncommon dual emission, while only one emission was observed in the solution of ligand H2L. The dual-emission mechanism was also realized by the structural analysis and photophysical study. Interestingly, although there is slight difference in structure (regular octahedral cage in 1 and slightly distorted octahedral cage in 2), the changes in N2 adsorption capability and photophysical performance between 1 and 2 are obvious, where 2 shows smaller Brunauer-Emmett-Teller surface area, broader absorption of antidimmer, and longer dual-emission lifetimes. Interestingly, either 1 or 2, the dual emission was clearly red-shifted by increasing the solvent polarity or the acidity of ambience, respectively.
Multi PCET in symmetrically substituted benzimidazoles
Elliott, MacKenna,Groy, Thomas L.,Hammes-Schiffer, Sharon,Moore, Ana L.,Moore, Thomas A.,Odella, Emmanuel,Secor, Maxim
, p. 12667 - 12675 (2021)
Proton-coupled electron transfer (PCET) reactions depend on the hydrogen-bond connectivity between sites of proton donors and acceptors. The 2-(2′-hydroxyphenyl) benzimidazole (BIP) based systems, which mimic the natural TyrZ-His190 pair of Photosystem II
The Photochemical Reduction of 2,1,3-Benzothiadiazole-4,7-dicarbonitrile in the Presence of Cationic Micelles, and Onward Electron-transfer Reactions
Robinson, Julian N.,Cole-Hamilton, David J.,Camilleri, Patrick,Dainty, Christine,Maxwell, Virginia
, p. 3385 - 3394 (1989)
Photolysis of solutions containing 2,1,3-benzothiadiazole-4,7-dicarbonitrile (BTDN) ethylenediaminetetra-acetic acid disodium salt (EDTA) and cetyltrimethylammonium bromide (CTAB) micelles at pH 5.5 produces the radical anion, BTDN.-, with BTDN acting both as an electron acceptor and as a chromophore.Variations in the efficiency of this reaction with pH, and are interpreted in terms of the formation of a complex between EDTA and BTDN which is broken down by the micelles.Net electron transfer does not occur within the complex.Alternative electron donors such as triethanolamine (TEOA) or 4-morpholine-ethanesulphonic acid (MES) can be employed, but not ascorbic acid or sulphite ion.The use of BTDN.- to reduce anthraquinones in stoichiometric or catalytic (with continuous photolysis) reactions is described.This allows an estimate of the redox potential of BTDN/BTDN.- when incorporated into micelles.
Small Organic Molecule Based on Benzothiadiazole for Electrocatalytic Hydrogen Production
Araujo, C. Moyses,Axelsson, Martin,Huang, Ping,Marchiori, Cleber F. N.,Tian, Haining
supporting information, p. 21229 - 21233 (2021/12/14)
A small organic molecule 2,1,3-benzothiadiazole-4, 7-dicarbonitrile (BTDN) is assessed for electrocatalytic hydrogen evolution on glassy carbon electrode and shows a hydrogen production Faradaic efficiency of 82% in the presence of salicylic acid. The key catalytic intermediates of reduced species BTDN–? and protonated intermediates are characterized or hypothesized by using various spectroscopic methods and density functional theory (DFT)-based calculations. With the experimental and theoretical results, a catalytic mechanism of BTDN for electrocatalytic H2 evolution is proposed.
Direct Conversion of Benzothiadiazole to Benzimidazole: New Benzimidazole-Derived Metal–Organic Frameworks with Adjustable Honeycomb-Like Cavities
Zhao, Yingnan,Han, Xiao,Yu, Feihu,Wei, Donghui,Cheng, Qing,Meng, Xiangru,Ding, Jie,Hou, Hongwei
supporting information, p. 5246 - 5250 (2019/03/21)
Up to now, the direct conversion of the thiadiazole ring to other heterocyclic rings has been a very challenging task. Herein, a CdII-mediated alcohol-substitution strategy for direct conversion from benzothiadiazole to benzimidazole is reported. Experimental and molecular modeling studies on the role of the chelated metal ion in this in situ alcohol-substitution reaction revealed that it serves as an all-rounder that is involved in the insertion of alcohol, activation of the thiadiazole ring by coordinative interaction, and the sulfur-extrusion process. Interestingly, the insertion of alcohol occurs much earlier than the sulfur-extrusion process, supported by a water-mediated proton-transfer process. This strategy also is suitable for constructing new benzimidazole-derived MOFs [Cd2(HMBIDC2?)2]?4 H2O (Cd-BID-MOF-1, HMBIDC2?=2-methyl-1H-benzimidazole-4,7-dicarboxylate) and [Cd2(HPBIDC2?)2]?1/3 H2O (Cd-BID-MOF-2, HPBIDC2?=2-(3-hydroxypropyl)-2H-benzimidazole-4,7-dicarboxylate). Because the terminal hydroxyl group on the imidazole ring protrudes into the circular channel in rhombohedral Cd-BID-MOF-2, the cavity is closer to hydrophilic than the honeycomb-like cavity in Cd-BID-MOF-1 with similar 3D structure. This rare observation will provide a new strategy to develop in situ ligand-reaction synthesis of functional MOFs and useful chelation-assisted catalytic reactions in heteroaromatic chemistry.