Review
Chemistry, Multidisciplinary
Nelson Y. S. Lam, Kevin Wu, Jin-Quan Yu
Summary: The design of synthetic routes by retrosynthetic logic is influenced by available transformations. Transition-metal-catalyzed C-H activation is a powerful strategy for C-C bond formation, but its uptake in total synthesis has been tepid due to synthetic intractability and a lack of comprehensive guidelines. This Review addresses these issues and offers a guide to identify retrosynthetic opportunities to generate C-C bonds by C-H activation processes. Comparing traditional approaches and recent C-H activation methods, this Review demonstrates more efficient retrosynthetic strategies enabled by C-H activation for C-C bond construction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Pidiyara Karishma, Alisha Gogia, Sanjay K. Mandal, Rajeev Sakhuja
Summary: This study successfully achieved a direct carbocyclization of 2-aryl-2,3-dihydrophthalazine-1,4-diones using isocyanates as the carbonyl source via Ru(II)-catalyzed sequential ortho-amidation followed by intramolecular nucleophilic substitution, delivering substituted indazolo[1,2-b]phthalazine-triones in good-to-excellent yields. Additionally, excellent yields of the corresponding amidated products were obtained for ortho-substituted 2-aryl-2,3-dihydrophthalazine-1,4-diones by modifying the reaction parameters. The use of isocyanates as the carbonyl source, high functional group tolerance on the two coupling partners, and diverse chemical transformation of the synthesized fused and functionalized phthalazinones are the key highlights of this work.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Review
Chemistry, Multidisciplinary
Sumon Basak, Subhabrata Dutta, Debabrata Maiti
Summary: The skeletal presence of 1,3-azoles in various bioactive compounds necessitates regioselective derivatization, with transition metal-catalyzed C-H functionalization emerging as a superior alternative to traditional methods. Recent research on C-2 functionalization of 1,3-azoles has shown significant progress in achieving high regioselectivity and introducing synthetically manipulative functionalities.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Review
Chemistry, Multidisciplinary
Sandeep Kumar, Akshay Kumar, Dharminder Sharma, Pralay Das
Summary: Directing groups are widely used for transition metal-catalyzed direct C-H bond functionalization, with recent advancements in utilizing free amine, hydroxyl and sulfhydryl as directing groups for the synthesis of heterocycles.
Article
Chemistry, Multidisciplinary
Soumya Kumar Sinha, Subir Panja, Jagrit Grover, Partha Sarathi Hazra, Saikat Pandit, Yogesh Bairagi, Xinglong Zhang, Debabrata Maiti
Summary: The article reports the development of a catalytic system for the synthesis of chalcogen motifs using a complimentary dual-ligand approach. The reaction is controlled by steric and electronic factors, and the use of suitable ligands allows the generation of products different from classical methods. The combination of ligands is crucial in the reaction protocol, and the mechanism of the reaction has been investigated through theoretical calculations and experiments.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Jianwen Liu, Wenzhi Luo, Yaru Yin, Xian-Zhu Fu, Jing-Li Luo
Summary: By studying the stepwise dissociative C-H bond activation, the mechanism of non-oxidative dehydrogenation of propane is elucidated. Frontier orbital analysis indicates that a smaller gap between HOMO and LUMO results in higher reaction activity. Modulating the gap between the HOMO of propane and the LUMO of catalysts is shown to be a critical strategy for the design of catalysts for non-oxidative propane dehydrogenation.
JOURNAL OF CATALYSIS
(2021)
Review
Chemistry, Organic
Jinhwan Park, Jongwoo Son
Summary: Metal-catalyzed C-sp2-H oxygenation is an important synthetic transformation that allows the incorporation of useful functional groups using a simple protocol. Cobalt catalysis, as a sustainable alternative, has gained attention due to its natural abundance and cost-effectiveness. In this Review, recent advances in cobalt-catalyzed C-sp2-H alkoxylation and acetoxylation are highlighted, along with discussions on various directing groups.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Applied
Ravichandran Logeswaran, Masilamani Jeganmohan
Summary: Olefins are important building blocks in synthetic organic chemistry and their functionalization has become a powerful method for constructing complex organic molecules. Despite some limitations, significant progress has been made in chelation-assisted C-H olefination reactions in recent years. This review describes the recent advances in these reactions, including the use of transition metals and base-assisted deprotonation pathways for the alkenylation and allylation of unactivated olefins.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Physical
Rui-Ping Huo, Zhen Song, Xiang Zhang, Cai-Feng Zhang
Summary: The mechanisms of ruthenium-catalyzed hydrogenation of benzonitriles were studied using DFT methods. It was found that two steps are required for the formation of the final product, benzylamine. Energy analysis showed that the overall reaction process is both kinetically and thermodynamically feasible, consistent with experimental observations. Electronic structure analysis revealed the factors influencing the choice between proton and hydride transfer during hydrogenation.
CHEMICAL PHYSICS LETTERS
(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.
Review
Chemistry, Multidisciplinary
Chandrasekaran Sivaraj, Thirumanavelan Gandhi
Summary: Functionalizing and derivatising organic molecules is crucial in organic synthesis, and the manipulation of acyl moieties has attracted significant interest due to their presence in various important compounds. Traditional acylation methods have their limitations, but the use of alternative acyl surrogates/reagents has made the process more attractive and environmentally friendly. These unconventional acylating reagents show practicality and versatility in transition-metal, metal-free, light-driven, and other challenging conditions.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Review
Chemistry, Physical
Jian-Zhen Lv, Yue-Ting Wei, Li-Yan Yang, Deng-Feng Yang, Hong-Liang Li
Summary: In recent years, significant progress has been made in the development of enantioselective C-H activation with the help of chiral ligands, enabling the formation of C-C and C-X bonds bearing a chiral center. By analyzing the mechanisms of these methods, it is hoped to accelerate related research and search for more efficient strategies.
Review
Chemistry, Multidisciplinary
Karunanidhi Murali, Luana A. Machado, Renato L. Carvalho, Leandro F. Pedrosa, Rishav Mukherjee, Eufranio N. Da Silva Junior, Debabrata Maiti
Summary: C-H functionalization has made significant advancements in synthetic organic chemistry, offering promising prospects in drug development and molecular architecture. The employment of novel metal catalysts and metal-free organic ligands has enabled selective activation of C-H bonds, overcoming previous challenges faced by chemists.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Tiago Vinicius Alves, Israel Fernandez
Summary: The reactivity and endo/exo selectivity of the Diels-Alder cycloaddition reactions involving furan and substituted furans as dienes have been computationally explored. The presence of substituents at either 2- or 3-positions of the heterocycle can modify both the reactivity and selectivity. The activation strain model of reactivity in combination with the energy decomposition analysis methods are used to quantitatively analyze the observed trends.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Zheng-Feng Zhang, Ming-Chung Yang, Ming-Der Su
Summary: Theoretical investigations were conducted on the heterolytic cleavage of H-2 by multiply bonded phosphorus-bridged G13-P-P-Rea and G15-P-Ga-Rea frustrated Lewis pairs. The study found that only Al-P-P-Rea, Ga-P-P-Rea, and InP-P-Rea can undergo energetically feasible H-2 activation reactions, with the reaction barriers affected by orbital overlap and atomic radii. Energy decomposition analysis revealed dominance of donor-acceptor interaction in the bonding of these reactions.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Stephanie Ten Brinck, Celine Nieuwland, Angela van der Werf, Richard M. P. Veenboer, Harold Linnartz, F. Matthias Bickelhaupt, Celia Fonseca Guerra
Summary: Experimental observations have shown that water-ice-embedded PAHs form radical cations, while ammonia-embedded PAHs form radical anions when exposed to vacuum UV irradiation. In this study, using density functional theory (DFT) computations, we explain this phenomenon by examining the electronic differences between water and ammonia, their interactions with PAHs, and the ionization pathways in these complexes. We demonstrate that the ionic state of PAH photoproducts depends on the degree of occupied-occupied MO mixing between the PAHs and the matrix molecules. Ammonia has better orbital overlap with PAHs, leading to mixed MOs and the formation of anionic PAHs, while water has poor overlap and mainly results in cationic PAHs through charge transfer.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Pascal Vermeeren, Trevor A. Hamlin, F. Matthias Bickelhaupt
Summary: The catalytic effect of ionization on the Diels-Alder reaction between 1,3-butadiene and acrylaldehyde has been studied using relativistic density functional theory (DFT). The removal of an electron from the dienophile significantly accelerates the reaction and changes the reaction mechanism. Detailed analyses reveal two mechanisms by which ionization enhances the reactivity.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Correction
Chemistry, Multidisciplinary
Dennis Svatunek, Nicole Houszka, Trevor A. Hamlin, F. Matthias Bickelhaupt, Hannes Mikula
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Thomas Hansen, Xiaobo Sun, Marco Dalla Tiezza, Willem-Jan van Zeist, Joost N. P. van Stralen, Daan P. Geerke, Lando P. Wolters, Jordi Poater, Trevor A. Hamlin, F. Matthias Bickelhaupt
Summary: The bond activation of substituted C(n degrees)-H and C(n degrees)-C(m degrees) bonds by palladium was investigated using density functional theory. The introduction of substituents has a significant impact on the bond activation process, with the C(n degrees)-X bonds becoming weaker but not necessarily leading to lower activation barriers.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Jie Jian, Darina Barkhatova, Roel Hammink, Paul Tinnemans, F. Matthias Bickelhaupt, Jordi Poater, Jasmin Mecinovic
Summary: This study investigates the noncovalent interactions between the central imidazole ring and flanking aromatic rings through physical-organic chemistry studies. The study reveals that through-space pi-pi interactions and NH-pi interactions contribute to the intramolecular stabilization of the imidazolium cation.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jie Jian, Roel Hammink, Paul Tinnemans, F. Matthias Bickelhaupt, Christine J. McKenzie, Jordi Poater, Jasmin Mecinovic
Summary: Arene-arene interactions play a fundamental role in molecular recognition. This study investigates arene-arene interactions in cyclophanes by designing and synthesizing specific compounds. The research reveals that fluorine substituents can fine-tune the aromatic character and acidity of phenol. X-ray crystallography and computational analyses demonstrate the presence of pi-pi stacking interactions and the importance of electrostatic and orbital interactions in the structure and stability of the compounds.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Roman Belle, Jos J. A. G. Kamps, Jordi Poater, Kiran Kumar, Bas J. G. E. Pieters, Eidarus Salah, Timothy D. W. Claridge, Robert S. Paton, F. Matthias Bickelhaupt, Akane Kawamura, Christopher J. Schofield, Jasmin Mecinovic
Summary: The substitution of nitrogen with phosphorus substantially affects the interactions between N-epsilon-methyllysine binding proteins and demethylases.
COMMUNICATIONS CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Lucas de Azevedo Santos, Teodorico C. Ramalho, Trevor A. Hamlin, F. Matthias Bickelhaupt
Summary: Quantum chemical methods were used to analyze the nature and origin of directionality in pnictogen, chalcogen, and halogen bonds in F(m)Z·F- complexes. The results show that covalent interactions, in addition to electrostatic attraction, contribute significantly to the bond energy. Interestingly, despite electrostatic interactions favoring bending, all these bonds exhibit directionality, which contradicts the sigma-hole model. These findings are applicable to various complexes, including ClI·NH3, HClTe·NH3, and H2ClSb·NH3.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Daniel E. Trujillo-Gonzalez, Gerardo Gonzalez-Garcia, Trevor A. Hamlin, F. Matthias Bickelhaupt, Holger Braunschweig, J. Oscar C. Jimenez-Halla, Miquel Sola
Summary: Boron-boron multiple bonds, such as diborenes and diborynes, are stabilized by sigma-donor ligands that provide electron density to these electron-deficient species. These compounds play a significant role in the study of chemical bonding and can activate small molecules like transition metals. Our density functional calculations showed that ligands with high or medium Lewis basicity effectively stabilize diborynes, while beryllium-based ligands show promise in stabilizing diborynes without affecting the triple bond character.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Bryan Phuti Moloto, Pascal Vermeeren, Marco Dalla Tiezza, Tessel Bouwens, Catharine Esterhuysen, Trevor A. Hamlin, F. Matthias Bickelhaupt
Summary: In this study, the activation of H(n)A-AH(n) bonds (AH(n) = CH3, NH2, OH, F) by PdLn catalysts with different ligands (L-n = no ligand, PH3, (PH3)(2)) was investigated using relativistic density functional theory. The results show that the activation energy for oxidative addition decreases from H3C-CH3 to H2N-NH2 to HO-OH, and the activation of the F-F bond is barrierless. The enhanced reactivity along this series of substrates is attributed to the combination of reduced activation strain, decreased Pauli repulsion, and enhanced backbonding interaction between the palladium catalyst and the substrate.
PURE AND APPLIED CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Thomas Hansen, Pascal Vermeeren, Kim W. J. Zijderveld, F. Matthias Bickelhaupt, Trevor A. A. Hamlin
Summary: The influence of ring strain on the competition between the S(N)2 and E2 pathways has been studied using quantum chemical methods. It was found that increasing ring strain decreases the activation energy of the S(N)2 pathway but generally increases the activation energy of the E2 pathway. This results in a mechanistic switch in the preferred reaction pathway for strong Lewis bases, favoring S(N)2 for small cyclic substrates and E2 for large cyclic substrates.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Jie Jian, Roel Hammink, Paul Tinnemans, F. Matthias Bickelhaupt, Jordi Poater, Jasmin Mecinovic
Summary: In this study, the noncovalent interactions between the tetrazole ring and neighboring aromatic ring substituents were investigated through synthetic, spectroscopic, structural, and quantum chemical analyses. The results showed that through-space NH-π interactions and π-π interactions contribute to the trends of pKa values and proton affinities of 2-arylphenyl-1H-tetrazoles. These findings are important for the rational design of tetrazole-based drugs and materials.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Physical
Humberto A. Rodriguez, F. Matthias Bickelhaupt, Israel Fernandez
Summary: The Burgi-Dunitz (BD) angle is essential in organic chemistry for understanding nucleophilic addition to carbonyl groups. However, the origin of the obtuse trajectory of the nucleophile is still not fully understood. This study quantifies the importance of physical factors quantum chemically to explain the obtuse BD angle. The obtuse angle is a result of reduced Pauli repulsion, a more stabilizing HOMO-π*-LUMO(C=O) interaction, and a favorable electrostatic attraction.
Article
Chemistry, Multidisciplinary
Celine Nieuwland, Pascal Vermeeren, F. Matthias Bickelhaupt, Celia Fonseca Guerra
Summary: The symmetry-decomposed Voronoi deformation density (VDD) charge analysis is a useful computational tool in chemistry that allows the quantification of atomic charge flow and the understanding of chemical bonding. It can decompose the charge flow into different types of orbital interactions and different irreducible representations of point-group symmetry. This method is now also applicable to interacting open-shell molecular fragments, providing detailed insights into chemical bonding beyond what is accessible from energy decomposition analysis (EDA).
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Editorial Material
Multidisciplinary Sciences
Jordi Poater, Pascal Vermeeren, Trevor A. A. Hamlin, F. Matthias Bickelhaupt, Miquel Sola
NATURE COMMUNICATIONS
(2023)