Review
Chemistry, Multidisciplinary
Jianbin Li, Chia-Yu Huang, Chao-Jun Li
Summary: This review summarises recently developed strategies for achieving C-C cross-couplings between an inert aliphatic C-H bond and another C-H bond through different C(sp3)-H functionalisation tactics.
TRENDS IN CHEMISTRY
(2022)
Article
Chemistry, Organic
Xinyu Chen, Hongqiang Liu, Hui Gao, Pinhua Li, Tao Miao, Hongji Li
Summary: An electrochemical cross-dehydrogenative coupling of indoles with xanthenes has been achieved at room temperature without the need for any catalyst or external oxidant, yielding moderate amounts of indole derivatives. Mechanistic experiments suggest a possible involvement of a radical pathway in this reaction system.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Wei Wei, Xiaodan Zhao
Summary: The carbon-carbon bond-forming cross-dehydrogenative coupling reaction using organoselenium catalysis involving a high-valent para-methoxyphenyl selenium species has been developed. This method enables the synthesis of alpha,alpha-disubstituted alpha-amino acid derivatives with excellent regioselectivities through vinyl or allylic C-H functionalization. The generality of this method has been demonstrated by the cross-coupling of an alkene with an oxindole and the direct functionalization of electron-rich arenes with azlactones.
Article
Chemistry, Multidisciplinary
Wenqiang Ma, Letian Xu, Sikun Zhang, Guoping Li, Tianyu Ma, Bin Rao, Mingming Zhang, Gang He
Summary: Bismoviologens are novel viologen analogues bridged by bismuth, featuring good redox properties and phosphorescence. Due to their unique properties, bismoviologens were fabricated into electrophosphorochromic devices and utilized for the first time as both a photocatalyst and electron mediator in visible light-induced reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Chemistry, Organic
C. M. A. Afsina, Thaipparambil Aneeja, Mohan Neetha, Gopinathan Anilkumar
Summary: Copper-catalyzed organic reactions have attracted widespread attention due to the abundance and affordability of copper, as well as its low toxicity, eco-friendliness, sustainable nature, and versatility as a catalyst. These reactions are primarily used for the synthesis of biologically important nitrogen heterocycles, amines, amides, imines, and alkynes.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Tian Tian, Zhiping Li, Chao-Jun Li
Summary: This review explores the development of cross-dehydrogenative coupling (CDC) reactions over the past 20 years and discusses future trends and directions, including the use of alternative energy inputs such as photoredox, mechano, microwave, electrochemical, continuous-flow, and solar quantum dots. These alternative forms of energy are gradually replacing the classical form of thermal energy, inspiring broader applications and innovations in the future.
Article
Chemistry, Organic
Chunqi Jia, Nini Wu, Gang Li, Xiuling Cui
Summary: In this study, a new method for the oxidative meta-dehydrogenative allylation of arenes with alkenes has been successfully developed using Ru(PPh3)3Cl2 as a catalyst and DTBP as an oxidant. The results demonstrate that this method provides an efficient and practical strategy for the preparation of versatile meta-allylated arenes.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Tianxiang Chen, Wenhua Yu, Ching Kit Tommy Wun, Tai-Sing Wu, Mingzi Sun, Sarah J. Day, Zehao Li, Bo Yuan, Yong Wang, Mingjie Li, Zi Wang, Yung-Kang Peng, Wing-Yiu Yu, Kwok-Yin Wong, Bolong Huang, Taoyuan Liang, Tsz Woon Benedict Lo
Summary: A cross-coupling reaction via dehydrogenative route over heterogeneous solid atomic catalysts provides practical solutions for the economic and sustainable development of simple organic substrates. However, the limited molecular definition of many solid catalysts hampers the current utilization of this technology. In this study, Cu-M dual-atom catalysts supported on hierarchical USY zeolite were developed to efficiently mediate dehydrogenative cross-coupling of unprotected phenols with amine partners. The reaction showed over 80% isolated yields over Cu-Co-USY, which exhibited superior reactivity compared to Cu1 and other Cu-M analogues. This research offers critical insights into the engineering of next-generation solid atomic catalysts with complex reaction steps.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Review
Chemistry, Multidisciplinary
Baitan Chakraborty, Christine K. Luscombe
Summary: Due to their versatile (opto)electronic properties, conjugated polymers have been widely used in organic electronic devices. Various cross-coupling reactions, such as Stille, Suzuki, Kumada couplings, and direct arylation reactions, have been effective for synthesizing conjugated polymers. Recent interest in donor-acceptor polymers has led to the development of cross-dehydrogenative coupling (CDC) polymerization, which allows the synthesis of alternating copolymers without prefunctionalization of monomers. This article discusses the development of CDC polymerization protocols and provides insights from small molecule CDC reactions for a better understanding of these reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Xin Zhang, Shuo Tong, Jieping Zhu, Mei-Xiang Wang
Summary: Under the catalysis of PdBr2 and a chiral phosphoramidite ligand, mono (2-bromoaroyl)-substituted calix[4]arene derivatives with upper-rim underwent an easy enantioselective desymmetrization reaction, yielding 9H-fluorene-embedded inherently chiral calixarenes with good yields and excellent enantioselectivities. The transannular dehydrogenative arene-arene coupling reaction most likely proceeded through oxidative addition of the C-aryl-Br bond to a ligated palladium catalyst, followed by a sequence of enantioselective 1,5-palladium migration and intramolecular C-H arylation. This new family of inherently chiral calixarenes has unique chiroptical properties due to their highly rigid structure induced by the 9H-fluorene segment.
Article
Nanoscience & Nanotechnology
Jingwen Chen, Yuanyuan Zhang, Xiaoling Chen, Siyun Dai, Zongbi Bao, Qiwei Yang, Qilong Ren, Zhiguo Zhang
Summary: CDC is an effective tool for carbon-carbon bond formation in chemical synthesis. MIL-101(Cr)-SO3H, a metal-organic framework with dual Lewis acidic Cr sites and sulfonic acid sites, has been reported as an efficient catalytic material for direct cross-coupling of xanthene and different nucleophiles using O-2 as the oxidant. The highly porous structure of MIL-101(Cr)-SO3H enables the free access of reactants to the catalytic active sites inside MOF pores, leading to excellent functional group compatibility and satisfactory yields of xanthene derivatives.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Organic
Chunhui Jiang, Xuefei Sha, Cheng Ni, Wei Qin, Xuejie Zhu, Shan Wang, Xuan Li, Hongfei Lu
Summary: A visible-light-induced dehydrogenative/decarboxylative coupling reaction of arylglycine derivatives and beta-keto acids is described, which allows for efficient synthesis of gamma-keto glycine derivatives under ambient conditions. This photocatalyst- and additive-free protocol also demonstrates further uses of this methodology and a plausible mechanism.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Applied
Heng Li, Jiajia Chen, Juncheng Zhang, Ping Liu, Peipei Sun
Summary: A direct amination of quinoxalin-2(1H)-ones via electrochemical C(sp(2))-H/N-H cross dehydrogenative coupling has been achieved using TMSN3 as the hydrogen atom transfer reagent. This synthetic strategy offers several outstanding features, including simplicity of operation, absence of transition metals and chemical oxidants, and high tolerance towards diverse functional groups. A variety of primary, secondary amines, and quinoxalinones can be tolerated, leading to the formation of secondary and tertiary amination products in good to excellent yields.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Pooja Y. Vemuri, Frederic W. Patureau
Summary: In this study, an unprecedented, simple and hetero-selective cross-dehydrogenative N-N coupling of amides and benzotriazoles using a hypervalent iodine species as the terminal oxidant was reported. The scope and mechanistic investigations of this reaction were discussed.
Article
Chemistry, Multidisciplinary
Ryota Sato, Tomoki Lida, Takaki Kanbara, Junpei Kuwabara
Summary: This Pd-catalysed cross-dehydrogenative coupling reaction allows the introduction of two polyfluoroarenes into simple polyaromatic hydrocarbons at sterically favourable positions. The investigation of the reaction mechanism revealed that the unique regioselectivity is determined by the reductive elimination step rather than the C-H bond cleavage step.
CHEMICAL COMMUNICATIONS
(2022)
Review
Chemistry, Physical
Shidheshwar B. Ankade, Anand B. Shabade, Vineeta Soni, Benudhar Punji
Summary: This review summarizes the transition-metal-catalyzed alkylations of C-H bonds on various arenes and heteroarenes using unactivated alkyl halides until October 2020. The review is divided into two major sections based on the substrates utilized for alkylation: alkylation of arenes and alkylation of heteroarenes. Substantial progress has been made in direct alkylation using primary, secondary, and tertiary alkyl halides as well as methylation and fluoroalkylation.
Article
Chemistry, Organic
Muniyappa Vijaykumar, Benudhar Punji
Summary: This article discusses the application of transition metal-catalyzed oxidation reactions in amides, achieving C-O bond formation through direct and regioselective C-H oxidation, and making significant progress.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Multidisciplinary
Rahul A. Jagtap, Benudhar Punji
Summary: The paper summarizes the developments in nickel-catalyzed regioselective functionalization of azoles and indoles, with a particular focus on the reaction mechanism.
Article
Chemistry, Organic
Muniyappa Vijaykumar, Benudhar Punji
Summary: The palladium-catalyzed chemoselective C(sp(2))-H and C(sp(3))-H acetoxylation of synthetically useful tertiary amides is reported under relatively mild reaction conditions. The reaction proceeds through the assistance of a weakly coordinated directing group and requires low catalyst loading. Diverse functionalities can be tolerated under the reaction conditions, and further functionalization to alcohols, alcohol-acids, and tertiary amines is demonstrated.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Dipesh M. Sharma, Chandrakant Gouda, Rajesh G. Gonnade, Benudhar Punji
Summary: Hemilabile and phosphine-free quinolinyl-based NNN-type pincer and non-pincer cobalt complexes have been developed for the room temperature catalytic transfer semi-hydrogenation of alkynes to Z-alkenes, delivering highly chemoselective and stereodivergent products.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Suryadev K. Verma, Benudhar Punji
Summary: A selective C(sp(2))-H bond alkylation of indoline, carbazole and (2-pyridinyl)arenes with unactivated alkyl bromides using MnBr2 catalyst without the need for an external ligand is reported. The alkylation reaction, which avoids the use of Grignard reagent, proceeds through a single electron transfer (SET) pathway and exhibits good tolerance towards diverse functionalities.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Rahul A. Jagtap, Chandini Pradhan, Rajesh G. Gonnade, Benudhar Punji
Summary: The iron-catalyzed dimerization of various isatin derivatives for the synthesis of 3,3'-biindolinylidene-diones (isoindigos) is described. This reaction can tolerate a wide range of functionalities, including cyclic and acyclic alkyls. The coupling between two distinct isatins shows excellent selectivity.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Organic
Chandini Pradhan, Benudhar Punji
Summary: This article presents the latest developments in the direct functionalization of heterocycles using abundant iron salts, providing a highly efficient and sustainable method for the synthesis of diverse privileged and biorelevant heterocycle-containing molecules.
Article
Chemistry, Organic
Muniyappa Vijaykumar, Chandini Pradhan, Rajesh G. Gonnade, Benudhar Punji
Summary: The palladium-catalyzed chemoselective oxygenation of C(sp2)-H and C(sp3)-H bonds in substituted isatin derivatives is described. This mild protocol allows for the C5 C(sp2)-H oxygenation of isatins through electrophilic intermolecular C-H palladation in concentrated solutions using PhI(OAc)2 or Selectfluor as an oxidant, while the N-CH3 C(sp3)-H oxygenation is achieved in dilute solutions via carbonyl-assisted intramolecular palladation in the presence of K2S2O8. This oxygenation reaction provides a direct and unified approach for synthesizing diverse oxygenated isatins with sensitive functionalities, including biorelevant compounds.
Article
Chemistry, Physical
Sadhna Bansal, Rajesh G. Gonnade, Benudhar Punji
Summary: Chemodivergent (de)hydrogenative coupling of azoarenes with benzyl alcohols via N=N bond activation is achieved using an inexpensive and well-defined (6-OH-bpy)NiCl2 catalyst. This protocol highlights C-N bond formation through a borrowing hydrogen strategy, leading to the synthesis of substituted imines and amines. Various azo compounds can couple with substituted benzyl alcohols through a tandem hydrogenation/dehydrogenation process, and the selectivity of imine and amine formation is controlled by the nickel catalyst and K2CO3 or (KOBu)-Bu-t base. Preliminary mechanistic study suggests the crucial role of metal-ligand cooperation (MLC) involving distinct radical pathways.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Chandini Pradhan, Rahul A. Jagtap, Pragnya Paramita Samal, Sailaja Krishnamurty, Benudhar Punji
Summary: In this study, a mild and efficient iron-catalyzed protocol for synthesizing alkylated indoles via C-H bond alkylation of indoles with unactivated alkenes was reported. The reaction demonstrated a high level of regioselectivity and occurred under solvent-free or trace green solvent conditions. The developed method provides easy access to privileged alkylated indoles with anti-Markovnikov selectivity and is in accordance with the principles of green chemistry.
Article
Chemistry, Multidisciplinary
Anand B. Shabade, Dipesh M. Sharma, Priyam Bajpai, Rajesh G. Gonnade, Kumar Vanka, Benudhar Punji
Summary: Chemoselective hydrogenation of C=C, C=O and C=N bonds in alpha,beta-unsaturated ketones, aldehydes and imines can be achieved at room temperature using a well-defined Mn(I) catalyst and hydrogen gas. The method shows tolerance towards various sensitive functional groups and can be applied to unsaturated ketones containing indole, pyrrole, furan, thiophene, and pyridine moieties. In the reaction, the C=C bond is selectively hydrogenated, while the C=O and C=N bonds in aldehydes and imines are preferentially reduced.
Article
Chemistry, Multidisciplinary
Rahul A. Jagtap, Shidheshwar B. Ankade, Rajesh G. Gonnade, Benudhar Punji
Summary: The synthesis of new NNN-oxazolinyl-pincer nickel complexes and their application in the transfer hydrogenation of ketones are described. Efficient synthesis of achiral and chiral ligands, treatment with (DME)NiCl2, and characterization by various analytical techniques were conducted, showing good yields. The developed nickel complexes were found to be efficient catalysts for the transfer hydrogenation of ketones, without enantioselectivity with the chiral catalysts.
NEW JOURNAL OF CHEMISTRY
(2021)
