Article
Chemistry, Inorganic & Nuclear
Sangeeta Kumari, Charu Sharma, Avinash K. Srivastava, Naveen Satrawala, Kamal N. Sharma, Raj K. Joshi
Summary: A Ru(II) complex was synthesized for C-H bond activation alkenylation of arenes using thioether directing groups, achieving high yields under milder conditions compared to previous methods utilizing precious noble metal catalysts. Broad substrate scope was demonstrated with good tolerance towards benzyl thioethers and vinyl, making it the first report of its kind utilizing a Ru-based catalyst for thioether alkenylation.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Youhao Wei, Zheng Wang, Kaifeng Wang, Jiang-Kai Qiu, Zhaoshan Wang, Haotian Li, Xiu Duan, Kai Guo, Xiaoguang Bao, Xinxin Wu
Summary: This study reports a copper-catalyzed allenic C(sp(2))-H cyanation with exceptional site-selectivity, addressing the challenge in synthetic chemistry of functionalizing allenic C(sp(2))-H bonds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Alexandra M. Zima, Oleg Y. Lyakin, Anna A. Bryliakova, Dmitrii E. Babushkin, Konstantin P. Bryliakov, Evgenii P. Talsi
Summary: Catalytic approaches to late-stage creation of new C-O bonds, especially via oxygenation of particular C-H groups in complex organic molecules, provide challenging tools for the synthesis of biologically active compounds and candidate drugs. The key role of the oxygen-transferring high-valent iron-oxygen species in selective oxygenation is now well established. In this Personal Account, recent data on the reactivity of bioinspired formally oxoiron(V) catalytically active sites toward organic substrates having C=C and C(sp(3))-H groups are analyzed, with a focus on the factors governing the oxidation chemo- and stereoselectivity.
Article
Chemistry, Physical
Roushan Prakash Singh, Soumen Sinhababu, Neal P. Mankad
Summary: This Perspective reviews recent advances and applications of Al/M heterobimetallic catalysis in various areas, including polymerization, epoxide activation and carbonylation. The mechanistic role of the aluminum site is highlighted, and a comprehensive perspective is constructed by including a broad range of Al-containing metalloligands and Al/M combinations.
Article
Chemistry, Multidisciplinary
Xinran Chen, Hasret Can Guelen, Jun Wu, Zi-Jing Zhang, Xin Hong, Lutz Ackermann
Summary: Ruthenium-catalyzed sigma-bond activation-assisted meta-C-H functionalization has gained significance in the formation of distal C-C bonds. However, the lack of mechanistic studies has hindered a complete understanding of the site-selectivity and reaction pattern. In this study, computational investigations were conducted on ruthenium-catalyzed C-H functionalization using alkyl bromides and aryl bromides. Monocyclometalated ruthenium(II) complexes were identified as the active species, with inner-sphere single electron transfer (ISET) facilitating the activation of organic bromides. The competition between reductive elimination and radical coupling determines the site-selectivity, which was further predicted using a multilinear regression model validated by experiments.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Liangliang Song, Gerardo M. Ojeda-Carralero, Divyaakshar Parmar, David A. Gonzalez-Martinez, Luc Van Meervelt, Johan Van Der Eycken, Jan Goeman, Daniel G. Rivera, Erik V. Van der Eycken
Summary: This report presents a ruthenium-catalyzed C-H activation/annulation process that can selectively modify the peptide backbone to produce functionalized isoquinolone scaffolds with high regioselectivity in a rapid and step-economical manner. The method allows for the production of fluorescent peptides, peptide conjugates with drugs, natural products, and other peptide fragments, providing a chemical approach for constructing novel peptide-pharmacophore conjugates.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Martin Vuagnat, Vincent Tognetti, Philippe Jubault, Tatiana Besset
Summary: A practical and straightforward synthesis of beta-(E)-trifluoromethylstyrenes by ruthenium-catalyzed C-H bond activation has been developed. The use of 2-bromo-3,3,3-trifluoropropene as a reservoir of 3,3,3-trifluoropropyne enables the safe and scalable monofunctionalization of a variety of heteroarenes. Mechanistic investigations and DFT calculations provide insights into the mechanism of this transformation, highlighting the role of a cyclometallated ruthenium complex.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Yaohang Cheng, Yuhang He, Jie Zheng, Hui Yang, Jun Liu, Guanghui An, Guangming Li
Summary: The method developed utilizes Ru(II) catalysis to facilitate the synthesis of challenging difluoroalkylated aldehydes and ketones with para-selectivity.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Rie Yoshimoto, Attila Taborosi, Qiyuan He, Yusuke Ano, Naoto Chatani, Seiji Mori
Summary: The reaction between aromatic amides and maleimides, catalyzed by palladium, leads to the formation of a product with double C-H bond activation, occurring at both the benzylic and meta positions. Computational chemistry studies reveal a stepwise mechanism involving a six-membered palladacycle, maleimide insertion, protonation of the Pd-N bond, and activation of the meta C-H bond. The site selectivity is determined by the interaction energy controlling the insertion of maleimide into the Pd-C(sp(3)) bond. The meta C-H bond activation step is identified as the rate-determining step based on the energetic span model. The 2-thiomethylphenyl group is found to function effectively as a directing group due to strong Pd-S bonding and the destabilizing effect of the deformation energy.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Nurbey Gulia, Jaroslaw Fornalski, Adrianna Gumienna, Malgorzata Ambroziak, Slawomir Szafert
Summary: This study reports a method of palladium-catalyzed C-H arylation assisted with a 3,4,4-trimethylpyrazol-5-on directing group, which selectively provides mono- and di-ortho-arylated products. The steric hindrance between the directing group and the already introduced aryl substituent enables control of mono- vs. diarylation selectivity by the reaction temperature. A series of monosubstituted and disubstituted derivatives were obtained in good yields. In addition, a one-pot procedure for unsymmetrical double-arylation to give corresponding products was developed, and the synthesis and X-ray study of intermediate palladium metallacycles were conducted. The decarboxylative cleavage of the pyrazolone directing group under mild conditions gave synthetically useful hydrazones. Overall, this solution provides an alternative synthetic pathway for ortho arylated derivatives of arylhydrazines.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Sara Lopez-Resano, Sara Martinez de Salinas, Felipe A. Garces-Pineda, Andrea Moneo-Corcuera, Jose Ramon Galan-Mascaros, Feliu Maseras, Monica H. Perez-Temprano
Summary: The potential access to Co-IV species to promote transformations challenging at Co-III in Cp*Co-catalyzed C-H functionalization reactions remains underexploited. We reveal the participation of Cp*Co-IV species in a Cp*Co-mediated C-S bond-reductive elimination through a combined experimental and computational strategy. These studies support the intermediacy of high-valent Cp*Co species in C-H functionalization reactions, particularly when involving nucleophilic coupling partners under oxidative conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Jun Wu, Nikolaos Kaplaneris, Julia Poehlmann, Takuya Michiyuki, Binbin Yuan, Lutz Ackermann
Summary: The prevalence of C-aryl glycosides in biologically active natural products and approved drugs has motivated the development of efficient synthesis strategies. Palladium catalysts with prefunctionalized substrates have been commonly used, while ruthenium-catalyzed C-aryl glycoside synthesis has been challenging. In this study, a versatile ruthenium(II)-catalyzed meta-C-H glycosylation method was disclosed, allowing for the synthesis of meta-C-aryl glycosides from readily available glycosyl halide donors. The ruthenium catalysis exhibited mild reaction conditions, exceptional levels of anomeric selectivity, and exclusive meta-site-selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Xue-Ya Gou, Yuke Li, Yu-Yong Luan, Wei-Yu Shi, Cui-Tian Wang, Yang An, Bo-Sheng Zhang, Yong-Min Liang
Summary: This study reports the combination of free radical cyclization and ruthenium-catalyzed meta-selective C-H functionalization for the synthesis of arylpyrrolidone derivatives, demonstrating high meta-site selectivity and wide applicability.
Article
Chemistry, Multidisciplinary
Jun Wu, Wen Wei, Julia Poehlmann, Rajeshwaran Purushothaman, Lutz Ackermann
Summary: In this study, a ruthenium(II)-catalyzed multicomponent Domino reaction was reported, which enables the efficient synthesis of structurally diversified C-alkyl glycosides in a single step.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Multidisciplinary
Chandrasekar Praveen, Aurelien Dupeux, Veronique Michelet
Summary: The review discusses the catalytic activity of gold in functionalizing various C-H bonds with high selectivity, highlighting factors such as steric/electronic properties of C-H bonds, oxidation state of gold, and stereoelectronic capacity of coordinated ligands. It also reveals the potential applications of Au(I) and Au(III) species in regio- and site-selective activation of challenging C-H bonds, as well as the selective C-H bond activation with different heterocycles described in recent literature.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Saghnik Saha, Jayabrata Das, Shaeel Ahmed Al-Thabaiti, Soha M. Albukhari, Qana A. Alsulami, Debabrata Maiti
Summary: Selective remote C-H functionalization of aliphatic chains is of great significance and remains a challenging task. The native functional group assisted C(sp(3))-H activation has emerged as a practical and efficient method for transforming aliphatic compounds. Aliphatic acids and amines have gained attention due to their unique coordination abilities with transition metals. This review summarizes the concepts and applications of remote C(sp(3))-H functionalization in aliphatic systems, providing a comprehensive understanding for beginners and experts.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Nupur Goswami, Soumya Kumar Sinha, Partha Mondal, S. Adhya, Ayan Datta, Debabrata Maiti
Summary: Regioselective and site-selective functionalization of distal C-H bonds has been a challenge due to the impact of covalently attached directing groups. Weak non-covalent interactions have been explored with Ir catalysis, but here we demonstrate a Pd-catalyzed meta-selective C-H functionalization of simple amines using anionic ligand and neutral substrate interactions. The site selectivity is governed by the H-bonding interaction between the anionic donating ligand and neutral motifs.
Review
Chemistry, Physical
Rahul Keshri, Debanjan Rana, Argha Saha, Shaeel Ahmed Al-Thabaiti, Abdulmohsen Ali Alshehri, Salem M. Bawaked, Debabrata Maiti
Summary: Transition-metal-catalyzed C(sp2)-H bond functionalization is a revolutionary strategy for efficient synthesis of complex heterocyclic frameworks. The use of free amine and alcohol as directing groups has shown significant advantages, allowing for the formation of C-C and C-heteroatom bonds and annulation cascades reactions. This review focuses on the utility of aromatic sp2-C-H functionalization directed by free amine and hydroxyl for constructing three to seven-membered N- and O-heterocycles.
Article
Chemistry, Multidisciplinary
Wajid Ali, Argha Saha, Haibo Ge, Debabrata Maiti
Summary: The merger of photocatalysis and transition-metal catalysis has led to the development of a versatile platform for environmentally friendly synthetic methods. By combining photoredox and Pd catalysis, a highly efficient, regioselective, and general meta-oxygenation protocol for various arenes has been developed. This protocol operates through a radical pathway and has been demonstrated to work for different substituted arenes using different substituents.
Article
Chemistry, Applied
Suman Maji, Sukumar Pradhan, Karishma Pidiyara, Siddhartha Maiti, Shaeel A. Al-Thabaiti, Debabrata Maiti
Summary: This work presents a palladium(II)-catalyzed regioselective C8-H olefination of 1-naphthamides. Notably, naphthamide fused lactam 2,3-dihydro-1H-benzo[de]isoquinolin-1-one derivatives were synthesized in a particular class of napthamides. The reaction showed good compatibility with a diverse range of acrylates and styrenes, providing the desired products with high yields and tolerance to various functional groups. The developed strategy was further employed for the synthesis of different drug derivatives.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Applied
Ankit Kumar Mittal, Gaurav Prakash, Pramod Pathak, Bishal Dutta, Nandita Ahalyan, Siddhartha Maiti, Debabrata Maiti
Summary: Here, we present a flow chemistry method for synthesizing tert-butyl nitrite with a high yield of 95% and a short residence time of 1min, corresponding to a space time yield of 13 g/h/mL. In addition, we demonstrate the application of tert-butyl nitrite in metal-free stereoselective nitration of alkenes. The traditional batch process, with a cycle time of 12 to 24 h, is limited for commercial production. Therefore, we developed a continuous-flow nitration process using a fixed bed column reactor, reducing the reaction time from 12 h to 3 min and achieving a faster and more efficient synthesis.
ORGANIC PROCESS RESEARCH & DEVELOPMENT
(2023)
Article
Chemistry, Physical
Nupur Goswami, Nikunj Kumar, Sukdev Bag, Puneet Gupta, Debabrata Maiti
Summary: This study investigates the palladium-catalyzed C(sp(2))-Holefination reaction of 2-arylbenzaldehyde with the aid of a temporary directing group. Computational and experimental methods are used to understand the reaction mechanism and selectivity. The results show that the reaction proceeds in three major steps and the selectivity is determined by the C-H activation step.
Article
Chemistry, Multidisciplinary
Jagrit Grover, Suman Maji, Chitrala Teja, Shaeel A. Al Thabaiti, Mohamed Mokhtar M. Mostafa, Goutam K. Lahiri, Debabrata Maiti
Summary: We have developed a novel Mn-SNS-based catalyst for the indirect hydrogenation of CO2 to methanol via formylation. Our catalyst, based on the stable and inexpensive SNS-type tridentate ligand, showed excellent recyclability and effectiveness in the formylation reaction. Various amines, including primary and secondary amines, worked well under the protocol to provide the desired formylated product in good yields. The formed formylated amines can also be further reduced at higher pressures of hydrogen.
ACS ORGANIC & INORGANIC AU
(2023)
Article
Chemistry, Multidisciplinary
Angus Olding, Curtis C. Ho, Debabrata Maiti, Alex C. Bissember
Summary: This article explores a series of case studies that examine key strategies enabling the structural authentication of important species in palladium- and nickel-catalysed C-C, C-N, and C-O cross-coupling reactions. It focuses on studies confirming the structures of challenging intermediates using X-ray crystallography, while providing mechanistic insights from these reports.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Jagrit Grover, Gaurav Prakash, Chitrala Teja, Goutam Kumar Lahiri, Debabrata Maiti
Summary: C-H thioarylation of hydrocarbon building blocks is a highly desirable synthetic transformation due to its prevalence in pharmaceuticals and organic functional materials. However, current developments rely on peroxide mediated transformations which have drawbacks of harsh reaction conditions and functional group intolerance. This study demonstrates a mild metal-free approach for C(sp(3))-H thioarylation using thioxanthone as a photo-catalyst, showing compatibility with various arenes, unactivated alkanes, and cycloalkanes. Post-synthetic modifications are also demonstrated through cross-coupling reactions and functional group interconversions.
Review
Chemistry, Multidisciplinary
Sayan Roy, Subir Panja, Sumeet Ranjan Sahoo, Sagnik Chatterjee, Debabrata Maiti
Summary: C-H functionalisation involves C-H activation and subsequent transformation, converting carbon-hydrogen bonds into carbon-carbon or carbon-heteroatom bonds. Metal-free approaches have gained attention as an alternative to transition metal-catalysed methods, providing a cost-effective and environmentally friendly way to functionalise C-H bonds.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Trisha Bhattacharya, Supratim Ghosh, Subhabrata Dutta, Srimanta Guin, Animesh Ghosh, Haibo Ge, Raghavan B. Sunoj, Debabrata Maiti
Summary: The significance of stereoselective C-H bond functionalization lies in its direct application potential to pharmaceuticals or complex chiral molecule synthesis. In this work, we harnessed the cooperative ligand approach to control two different stereogenic elements in the same molecule, resulting in the synthesis of axially chiral biaryls.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Uttam Dutta, Gaurav Prakash, Kirti Devi, Kongkona Borah, Xinglong Zhang, Debabrata Maiti
Summary: A method for directing group-assisted para-selective C-H alkynylation using Rh catalyst has been reported. The para-selectivity was achieved with the assistance of a cyano-based directing template, and remained unaltered regardless of the steric and electronic influence of the substituents. The study provides insights into the mechanistic intricacies and shows potential applications for post-synthetic modification.
Review
Chemistry, Multidisciplinary
Soumya Kumar Sinha, Pintu Ghosh, Shubhanshu Jain, Siddhartha Maiti, Shaeel A. Al-Thabati, Abdulmohsen Ali Alshehri, Mohamed Mokhtar, Debabrata Maiti
Summary: C-H activation plays a crucial role in the synthetic strategies for multi-step transformations, but its importance lies in its application in large-scale industrial processes and the synthesis of complex natural products. Recent advancements in C-H activation methodologies have led to the discovery of more efficient synthesis methods and accelerated the synthesis of complex organic compounds.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Uttam Dutta, Gaurav Prakash, Kirti Devi, Kongkona Borah, Xinglong Zhang, Debabrata Maiti
Summary: In this study, the first report on the rhodium-catalyzed para-selective C-H alkynylation is presented, and its mechanistic insights are obtained from experimental and computational studies. The para-selectivity is achieved with the assistance of a cyano-based directing template, which remains unchanged regardless of the steric and electronic influence of the substituents.
