Article
Multidisciplinary Sciences
Yun Zhang, Xi-Chao Wang, Cheng-Wei Ju, Dongbing Zhao
Summary: This study presents a nickel-catalyzed bis-silylation of internal alkynes to generate versatile silylated alkene intermediates, which can be selectively manipulated for downstream functionalization.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Kang Wang, Saisai Yan, Ting Han, Qian Wu, Neng Yan, Miaomiao Kang, Jinyin Ge, Dong Wang, Ben Zhong Tang
Summary: The development of straightforward and efficient synthetic methods toward ring-fused heteroaromatic polymers with attractive functionalities has great significance in both chemistry and materials science. In this study, a facile cascade C-H-activated polyannulation route was developed to in situ generate ring-fused aza-heteroaromatic polymers with multiple aryl pendants. The obtained polymers showed excellent thermal and morphological stability, good solution processability, high refractive index, small chromic dispersion, as well as remarkable acid-base-responsive fluorescence. The triphenylamine-substituted heteroaromatic polymer was successfully applied as a sensitive fluorescence probe for intracellular pH mapping and quantitative analysis. Additionally, diverse azonia-containing polyelectrolytes were produced through the N-methylation reaction of the ring-fused polybenzimidazoles, exhibiting efficient cancer cell-killing effects.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Wei Zhao, Bi-Jie Li
Summary: Despite advances in the Murai-type hydroarylations, enantioselective addition of native (hetero)arenes to internal alkenes remains challenging. This study presents a directing group repositioning strategy for the enantioselective addition of heteroarenes to internal enamides. The C-H bond at the C2 position of heteroarenes is selectively cleaved and added to the beta-position of enamides, yielding beta-heteroaryl amides with high enantioselectivity. Mechanistic studies reveal separate elementary steps determining rate and enantioselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Denis A. Gazizov, Victor V. Fedotov, Konstantin A. Chistyakov, Evgeny B. Gorbunov, Gennady L. Rusinov, Valery N. Charushin
Summary: A simple and convenient method for synthesizing new azolopyrimidine-6,7-diamines has been developed by reductive cleavage of the azo-group in a series of compounds. The approach allows for the use of a wide range of aminoazoles as starting reagents and demonstrates synthetic potential in obtaining azolo[a]annulated pteridines.
Article
Chemistry, Multidisciplinary
Yang Zhao, Xinyue Niu, Hong Yang, Jing Yang, Zhizeng Wang, Qilin Wang
Summary: In this study, a substrate-directed diverse synthetic strategy was reported for the synthesis of two kinds of structurally intriguing fused indole polycycles through Rh(ii)-catalyzed cascade reactions. The subtle structural changes in enaminones result in different reactivities.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Peng Qian, Shan Jiang, Hua Fan, Siqi Jiang, Longlong Xu, Jiaojiao Liu
Summary: A facile method for the synthesis of bis-pyrazolo[3,4-b:4',3'-e]pyridines from easily available aromatic aldehydes and pyrazol-5-amines was developed via electrochemistry, resulting in moderate yields.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Automation & Control Systems
Deepak Sridhar, Deepak Kumar, G. Lloyds Raja, Sudipta Chakraborty
Summary: This paper presents a new cascade control structure (SCCS) for controlling unstable and stable plants. The proposed structure requires tuning only four controller parameters and exhibits significant improvements in closed-loop performance.
INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Sandra Rodriguez-Alvarez, Jose M. Palazon, Rosa L. Dorta
Summary: A method has been developed to synthesize tetrahydroisoquinolines (THIQs) fused to tetrahydrofuran rings from aminosugar derivatives. This method involves the deprotection of benzyl ethers followed by a double-cyclization sequence using FeCl3 as the sole reagent, allowing for the construction of novel fused polycyclic heterocycles with precise stereochemical control.
Article
Chemistry, Applied
Xiong-Wei Liu, Xiao-Tong Lin, Cheng Zhao, Xiao-Wei Hu, Yi-Bing Xu, Yi-Lin Zheng, Xin-Ni Liu, Guo-Shu Chen, Long Chen, Yun-Lin Liu
Summary: The construction of benzopyrone-fused hydrobenzofuranones via DABCO-catalyzed [3+2] cyclization/deformylation cascade of p-quinols with 3-formylchromones is described. The reaction provides the desired products in 53-90% yields with complete diastereoselectivities under mild conditions. Furthermore, an enantioselective version with 81% ee is also achieved in the presence of Takemoto's chiral thiourea catalyst.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Ryuta Wada, Shigesaki Kaga, Yasuhiro Kawai, Kimitaka Futamura, Toshiaki Murai, Fumitoshi Shibahara
Summary: A new route to synthesize thiophene-ring-fused compounds using thionyl chloride as a sulfur source was developed. The study found that in some cases, the target compounds could be synthesized directly using an excess amount of thionyl chloride, and also observed unexpected mechanochromism behavior in one of the obtained compounds.
Article
Engineering, Multidisciplinary
Bruno Emmanuel de Oliveira Barros Luna, Cursino Brandao Jacobina, Alexandre Cunha Oliveira
Summary: This article presents a methodology to control the internal energy balance of a modular multilevel cascade converter (MMCC) with distributed energy resources. The converter consists of bidirectional cascaded chopper cells with floating capacitors connected to a three-phase MMCC and distributed photovoltaic arrays. By using power flow equations and a control methodology, the internal energy balance of the MMCC can be maintained even in the presence of power imbalance between the cells. The converter topology and control methodology are suitable for hybrid renewable energy systems.
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Sergey D. Tokarev, Anatoly Botezatu, Andrey Khoroshutin, Yury Fedorov, Olga A. Fedorova
Summary: New polycyclic aromatic derivatives, crown naphthothiophenes, annulated both with thiophene and with 15-crown-5 ether moieties, were successfully synthesized via the Mallory photocyclization. Their complexation with Ba2+ and Mg2+ cations was investigated using optical and electrochemical methods, revealing the chemical stability of the compounds in the oxidized state depending on their structure.
MENDELEEV COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Vera L. Mamedova, Victor V. Syakaev, Il'dar Kh. Rizvanov, Essam M. Mahrous, Gul'naz Z. Khikmatova, Sevil Mamedova, Leisan R. Shamsutdinova, Elena L. Gavrilova, Vakhid A. Mamedov
Summary: Reduction of 3-(2-nitrobenzyl)quinoxalin-2-ones, pyrido-, and 1,2,5-oxadiazolo-fused 3-(2-nitrobenzyl)pyrazinones with sodium dithionite (Na2S2O4) in an acidic medium leads to Mamedov rearrangement in the first two cases, and intramolecular condensation in the third case, resulting in the formation of rare bi-, bis-, and condensed heterocyclic systems that are difficult to obtain by other methods.
Article
Chemistry, Applied
Wanying Yan, Zhonghua Qu, Feng Zhao, Guo-Jun Deng, Guo-Jiang Mao, Huawen Huang
Summary: A mild visible-light induced 4CzIPN/H+ photoredox system was developed for the formal C-O bond cleavage of hydroxyketones, serving as a carbon radical precursor. This process was successfully applied in the coupling/cyclization reaction of N-arylacrylamides, providing a practical access to acyl oxindoles. The protocol offers advantages such as no need for any metal catalyst and additive, high yield, broad substrate scope, gram scalability, and sole byproduct release of H2O.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Zhonghua Qu, Xiaochen Ji, Lin Tian, Guojiang Mao, Guo-Jun Deng, Huawen Huang
Summary: The efficient synthesis of biologically interesting 3-thionated oxindoles was achieved by photoredox-mediated oxidative thiolation and cyclization of N-arylacrylamides with thiols, involving C-S and C-C bond formation. The reaction utilizes non-prefunctionalized thiolating reagents and TBHP as a key radical initiator under visible-light catalysis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Qiao-Lin Wang, Huawen Huang, Guojiang Mao, Guo-Jun Deng
Summary: A method for the radical-radical couplings of alkylarenes and diarylmethanes with 4-cyanopyridine has been developed at room temperature. The reactions were promoted by combining photoredox catalysis and hydrogen atom transfer catalysis. A wide range of diarylmethanes and triarylmethanes with heteroaryl groups were synthesized with good to excellent yields. The pyridine moiety was also successfully introduced into bioactive molecules and complex compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Applied
Shuowen Wang, Rong Li, Huawen Huang, Guojiang Mao, Wen Shao, Guo-Jun Deng
Summary: A regioselective synthesis of 2-amino-para-iminonaphthoquinones and 4-amino-1,2-naphthoquinones was achieved by the substrate-dependent divergent multi-functionalization of beta-tetralone with primary and secondary amines under metal-free conditions. This strategy offers environmentally friendly and mild reaction conditions (using O-2 as oxidant, ethanol as solvent at ambient temperature), and allows for a wide range of substrates and various pharmaceutical derivatizations.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Review
Biochemistry & Molecular Biology
Pu Chen, Huawen Huang, Qi Tan, Xiaochen Ji, Feng Zhao
Summary: The synthetic strategies of oxime derivatives participating in radical-type reactions have been rapidly developed in the last few decades. The N-O bond cleavage of oxime esters leading to the formation of nitrogen-centered radicals triggers adjacent C-C bond cleavage to produce carbon-centered free radicals, which has been virtually used in organic synthesis in recent years. In this review, the free radical reactions involving acyl oxime esters and cyclic ketoxime esters after 2021 were included, with emphasis on the substrate scope and reaction mechanism.
Article
Chemistry, Organic
Qiao-Lin Wang, Huawen Huang, Mengqi Zhu, Tianci Xu, Guojiang Mao, Guo-Jun Deng
Summary: This study reports a visible-light induced C-(sp(3))-H functionalization of alkylarenes with trifluoromethyl ketones, enabling the synthesis of valuable benzyl-substituted trifluoromethyl alcohols in a stoichiometric manner. Petroleum-derived alkylarenes are used as latent benzylation reagents. Bromine radical serves as the hydrogen atom transfer reagent, allowing for coupling of primary, secondary, and tertiary benzyl C-H bonds. The late-stage modification of bioactive molecules highlights the potential application of this approach.
Article
Chemistry, Organic
Ning Xian, Jiang Yin, Xiaochen Ji, Guo-Jun Deng, Huawen Huang
Summary: The visible-light-induced photoredox carbon radical formation from aqueous sulfoxonium ylides has been demonstrated for the first time. Direct reduction of sulfoxonium ylides by H2O generates hydrocarbon compounds efficiently, while the use of additional alkenes as radical acceptors changes the chemical reactivity to achieve alkene carboarylation of N-arylacrylamides. Mechanistic studies reveal two different reaction pathways involved in the carbon radical formation from aqueous sulfoxonium ylides resulting in reduction to release dimethyl sulfone and carboarylation to form DMSO.
Article
Chemistry, Physical
Zhaosheng Liu, Xiaochen Ji, Feng Zhao, Guojun Deng, Huawen Huang
Summary: A novel metal-free photoredox-catalyzed cyclization reaction of N-aryl acrylamide is presented, which produces valuable oxindole derivatives through the mediation of H2O and aldehyde. Sustainable visible light was employed as the energy source, and the organic light-emitting molecule 4CzIPN acted as the efficient photocatalyst. The main features of this reaction are environmentally-friendly conditions and high yields.
Article
Chemistry, Applied
Wanying Yan, Jiaru Shou, Wenyi Qin, Jiayu Mo, Huawen Huang
Summary: Chemoselective cyclizations of 1,3-dicarbonyl compounds with hydroxyketones have been reported for the selective formation of two 2,3,5-trisubstituted furans. 2-acylfurans were obtained through TsOH-mediated cyclization in DCM, while the addition of a copper catalyst in acetone shifted the selectivity towards the generation of 3-acylfurans. These reactions have advantages such as simple conditions, high yield, broad substrate scope, gram scalability, and H2O as the sole byproduct.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Xinzhuang Wu, Xinyi Zhang, Xiaochen Ji, Guo-Jun Deng, Huawen Huang
Summary: A cascade arylazidation reaction of activated alkenes with trimethylsilyl azide (TMSN3) under visible-light irradiation has been developed. Mechanistic investigations reveal that the reaction proceeds via single electron transfer (SET) between TMSN3 and the excited photocatalyst, followed by radical addition/aryl migration/desulfonylation to yield valuable α-aryl-β-azido amides and azidated oxindoles as versatile building blocks in organic synthesis. The obtained arylazidated products can be further converted to valuable β-amino amide and 1,2,3-triazole derivatives with simple treatment.
Article
Chemistry, Organic
Jinjin Chen, Shuxin Jiang, Weiliang Shi, Pingyu Jiang, Xinping Liu, Huawen Huang, Guo-Jun Deng
Summary: Here, a atom- and step-economic three-component cascade reaction was developed for the synthesis of pyrrolo[2,3-c]quinoline compounds. The reaction involves ring-expansion/cyclization through novel N1-C2 cleavage of indoles and the metal-free catalytic system offers a wide range of functional group tolerance.
Article
Chemistry, Multidisciplinary
Xiaoyuan Wan, Dahan Wang, Huawen Huang, Guo-Jiang Mao, Guo-Jun Deng
Summary: In this study, a novel visible light-induced photocatalytic system for intramolecular hydroarylation of unactivated alkenes is reported. Thiosulfonate compounds were identified as the crucial radical precursor mediating the Minisci-type intramolecular cyclization reaction. The reaction conditions were optimized, leading to the formation of a wide range of pyridyquinazolinone and pyrroloquinazolinone products in moderate to good yields.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Yongbo Tan, Huawen Huang
Summary: Herein, we present a photocatalyst- and additive-free method for the synthesis of valuable 3,3-disubstituted oxindoles bearing trifluoromethyl alcohol moieties. This method utilizes readily available acrylamides and cheap trifluoropyruvates, and shows broad functional group tolerance and moderate to good yields.
CHEMICAL COMMUNICATIONS
(2023)
