Article
Chemistry, Applied
Dipak B. Deokar, Soumi Laha, B. Sridhar, Dharmendra Kumar Tiwari, Pravin R. Likhar
Summary: A palladium-catalyzed coupling reaction followed by dual annulation has been developed for the synthesis of various triazolo/pyrrolo fused benzofuro-quinolines from readily available starting materials. This method involves palladium-catalyzed Sonogashira coupling, benzan-nulation, and C-H activation triggered second annulation reaction cascades in a single pot. The polycyclic compound formed by this method consists of three different heterocyclic structures: benzofuran, quinoline, and triazole/pyrrole. The method provides a simple access to obtain a range of fused benzofurotriazalo/pyrroloquinolines in good to moderate yields.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Physical
Chiara Palladino, Tommaso Fantoni, Lucia Ferrazzano, Beatrice Muzzi, Antonio Ricci, Alessandra Tolomelli, Walter Cabri
Summary: The copper-free Heck-Cassar-Sonogashira (HCS) reaction is a powerful method for C-C bond formation in organic synthesis and has several industrial applications. This study investigated the mechanism of the copper-free HCS reaction by conducting stoichiometric and catalytic reactions and analyzing the role of the base. The results showed that the base can accelerate the reduction of the precatalyst and decrease the energy barrier for the alkyne carbopalladation step.
Article
Chemistry, Inorganic & Nuclear
Lin Li, Yan Mei, Junlei Zhang, Kehan He, Fei Pan
Summary: In this study, a palladium-catalyzed Sonogashira-type cross-coupling reaction of 1-bromo-2,2-difluoroethylene with various aromatic and aliphatic terminal alkynes was developed. This reaction proceeds smoothly under mild conditions and provides access to gem-difluoroenyne derivatives. The commercially available and easy-to-handle nature of 1-bromo-2,2-difluoroethylene makes it a useful difluoroethenyl source. This new synthetic protocol offers a novel strategy for the direct construction of gem-difluoroenynes with good functional group tolerance and high yields.
JOURNAL OF FLUORINE CHEMISTRY
(2023)
Article
Chemistry, Physical
Xing Sheng, Jiayi Xian, Shuting Liu, Xiangyu Zhang, Bin Li, Jun Wang, Xiuwen Chen, Feng Xie
Summary: This study describes a green palladium-catalyzed nitroarene/nitrile reductive cross-annulation chemistry for the straightforward synthesis of pyrrolo[1,2-a]quinoxaline derivatives. Nitriles are activated as carbon synthons to form intramolecular C-N and C-C bonds. The synthetic protocol offers broad substrate scope, excellent functional group tolerance, and uses water and inexpensive HCOONa/HCOOH as the solvent and hydrogen donors, respectively. The catalyst can be conveniently recycled and reused multiple times without significant deactivation. This study provides an important platform for converting bulk chemical motifs into value-added functional frameworks.
JOURNAL OF CATALYSIS
(2023)
Review
Chemistry, Organic
Xian Zhao, Wei Liu
Summary: Catalytic Sonogashira cross-coupling reactions are efficient and versatile for constructing complex alkynes from readily available starting materials. However, the development of transition-metal-catalyzed Sonogashira cross-coupling reactions of alkyl electrophiles is still limited. Current research focuses on the application of palladium, nickel, and copper catalysts, as well as achieving asymmetric Sonogashira cross-coupling reactions.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Physical
Xueling Mo, Han Huang, Guozhu Zhang
Summary: Synthesis of chiral tetrasubstituted carbon stereocenters is a challenging task in organic chemistry. This study demonstrates that asymmetric alkynylation using catalytic reactions can efficiently produce tertiary stereocenters and all-carbon quaternary stereocenters with synthetic and medicinal value.
Article
Chemistry, Organic
Haibo Liu, Xiaomin Mai, Jiayi Xian, Shuting Liu, Xiangyu Zhang, Bin Li, Xiuwen Chen, Yibiao Li, Feng Xie
Summary: This article reports a palladium-catalyzed selective hydrogenative coupling of nitroarenes and phenols based on a transfer hydrogenation strategy, allowing the synthesis of spirocyclic pyrrolo- and indolo-fused quinoxalines, a class of compounds found in many natural alkaloids. The synthetic protocol offers a broad substrate scope and utilizes biomass-derived reactants and commercially available catalysts without the need for high-pressure or explosive hydrogen.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
C. Rajalakshmi, S. S. Jibin, Rehin Sulay, Sujatha Asha, Vibin Ipe Thomas, Gopinathan Anilkumar
Summary: The mechanism of copper-catalyzed Sonogashira coupling reaction using trans-1,2-diamino cyclohexane ligand was investigated with DFT method. The use of chelating diamine ligands can accelerate cross-coupling reactions, showing a concerted mechanism different from Pd-catalyzed reactions.
Review
Chemistry, Multidisciplinary
Pui Ying Choy, Kin Boon Gan, Fuk Yee Kwong
Summary: Sonogashira cross-coupling protocol allows the construction of C(sp(2))-C(sp) bond through the reaction between aryl/vinyl halide and terminal alkyne. The resulting internal alkynes are versatile for the synthesis of various functionalized alkyne-containing scaffolds or as valuable synthetic synthons. The reaction conditions can be adjusted to activate hindered and/or electron-rich electrophiles, and Pd-catalyzed copper-free Sonogashira coupling reaction has gained attention for being more environmentally friendly and allowing convergent synthesis in a one-pot manner.
CHINESE JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Physical
Xiaojun Zeng, Chao Wang, Wenhao Yan, Jian Rong, Yanshan Song, Zhiwei Xiao, Aijie Cai, Steven H. Liang, Wei Liu
Summary: Despite the historical challenge of engaging unactivated alkyl halides in Sonogashira coupling reactions, we have developed a strategy that combines Cu-catalyzed alkyne transfer with aryl radical activation of carbon-halide bonds. This allows for a general approach to coupling alkyl iodides with terminal alkynes. This unprecedented reaction tolerates a wide range of functional groups and has been applied to the late-stage cross-coupling of pharmaceutical agents and the synthesis of positron emission tomography tracers.
Article
Chemistry, Physical
Xiaojun Zeng, Chao Wang, Wenhao Yan, Jian Rong, Yanshan Song, Zhiwei Xiao, Aijie Cai, Steven H. Liang, Wei Liu
Summary: A new strategy combining Cu-catalyzed alkyne transfer with aryl radical activation of carbon-halide bonds enables the coupling of alkyl iodides with terminal alkynes. This unprecedented Sonogashira-type cross coupling reaction is tolerant towards a wide range of functional groups and has applications in pharmaceutical synthesis and the synthesis of positron emission tomography tracers.
Article
Chemistry, Applied
Lyudmila A. Grishchenko, Lidiya N. Parshina, Lyudmila I. Larina, Yana A. Kostyro, Boris A. Trofimov
Summary: New salicylate derivatives of arabinogalactan have been synthesized with high yield, showing high anti-coagulation activity. The reaction yield varies depending on the base used, and unexpected additional reactions were observed in the presence of piperidine.
CARBOHYDRATE POLYMERS
(2021)
Article
Chemistry, Organic
Ying Chen, Sailuo Li, Lanting Xu, Dawei Ma
Summary: N-1-(2,6-Dimethylphenyl)-N-2-(pyridin-2-ylmethyl)-oxalamide (DMPPO) was found to be a more effective ligand for copper-catalyzed coupling reaction than previously reported ones. Only 3 mol % CuCl and DMPPO are needed for complete coupling at 100 degrees C (for bromides) and 80 degrees C (for iodides). Both (hetero)aryl and alkyl substituted 1-alkynes showed good reactivity, resulting in the formation of diverse internal alkynes.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Jiwon Ahn, Seok Beom Lee, Injae Song, Simin Chun, Dong-Chan Oh, Suckchang Hong
Summary: The direct synthesis of pyrrolo[1,2-alpha]quinoxaline was achieved through oxidative coupling between methyl arene and 1-(2-aminophenyl) pyrroles. This method displayed high reactivity towards various functional groups and was carried out in air, utilizing easily accessible catalysts, reagents, and solvents.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Materials Science, Paper & Wood
Zhian Xu, Jinxi Xu, Waner Zheng, Yiqun Li
Summary: A novel and efficient cellulose-based Pd@Cell-EDTA catalyst was easily prepared through the esterification of cellulose with ethylenediaminetetraacetic dianhydride and subsequent coordination with PdCl2. The Pd@Cell-EDTA catalyst showed excellent activity in Suzuki reactions and Sonogashira reactions, and it could be reused multiple times without significant loss of catalytic performance.
