Article
Chemistry, Physical
Artemy R. Fatkulin, Oleg I. Afanasyev, Alexey A. Tsygankov, Denis Chusov
Summary: This study demonstrates a significant increase in the catalytic activity of ruthenium catalysts in reductive amination after the addition of iodide to the reaction mixture. High turnover numbers and preparative yields of the products were achieved.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Elisa Y. Lai, Binbin Yuan, Lutz Ackermann, Magnus J. Johansson
Summary: In this study, a new method for directed ruthenium-catalyzed C-H aminocarbonylation has been developed under mild conditions through high-throughput experimentation. This method allows the introduction of special amide functional groups and is applicable to various substitution patterns and different weakly Lewis basic directing groups in anilides.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Arkadiusz Listkowski, Natalia Masiera, Michal Kijak, Roman Luboradzki, Barbara Lesniewska, Jacek Waluk
Summary: The researchers analyzed the structural, spectroscopic, and photophysical data of six porphycenes and found a clear correlation between the strength of intramolecular NH....N hydrogen bonds and the efficiency of the nonradiative depopulation of the lowest-excited singlet state. They proposed a new model based on the delocalization of inner protons in the macrocycle cavity as responsible for nonradiative deactivation, which was confirmed by literature data for other alkyl- or aryl-substituted porphycenes.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Lia Sotorrios, Fedor M. Miloserdov, Anne-Frederique Pecharman, John P. Lowe, Stuart A. Macgregor, Mary F. Mahon, Michael K. Whittlesey
Summary: The syntheses, reactivity, and electronic structure analyses of [Ru(PPh3)(2)(ZnMe)(4)H-2] and [Ru(PPh3)(2)(ZnPh)(4)H-2] are reported. [Ru(PPh3)(2)(ZnMe)(4)H-2] exhibits an 8-coordinate Ru center with axial phosphines and a symmetrical (2 : 2) arrangement of ZnMe ligands in the equatorial plane. The ZnMe ligands in [Ru(PPh3)(2)(ZnMe)(4)H-2] undergo facile, sequential exchange with ZnPh2 to give [Ru(PPh3)(2)(ZnPh)(4)H-2], which shows a 3 : 1 arrangement of ZnPh ligands. Mechanisms for ZnMe/ZnPh exchange and isomerization are proposed using DFT calculations, and the relationships of these {Ru(ZnR)(4)H-2} species to isoelectronic Group 8 transition metal polyhydrides and related Schlenk equilibria in the Negishi reaction are discussed.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Yi Liu, Lianrui Cheng, Yi Huang, Yuting Yang, Xianfa Rao, Shuqing Zhou, Tayirjan Taylor Isimjan, Xiulin Yang
Summary: A metal-organic framework-derived strategy of constructing a Pt-free catalyst with Ru clusters anchored on porous Cu-Cu2O@C is proposed. The designed Ru/Cu-Cu2O@C exhibits superior alkaline hydrogen oxidation/evolution reaction (HOR/HER) performance, surpassing state-of-the-art Pt/C by 24 times in HOR activity and outperforming most documented Ru-based electrocatalysts in HER performance. Systematic characterization and density functional theory (DFT) calculations indicate that efficient electron transfer between Ru and Cu species contributes to the enhanced HOR and HER kinetics.
Article
Chemistry, Inorganic & Nuclear
Briana R. Schrage, Eugeny Ermilov, Victor N. Nemykin
Summary: The formation and deactivation of charge-separated state was investigated in a series of compounds using transient absorption spectra. The lifetime of the charge-separated state was nearly constant for all compounds and independent of the central ion and solvent. A minor long-lived component was observed in polar solvent.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yang Wei, Melissa Conklin, Yong Zhang
Summary: Engineered heme protein biocatalysts provide an efficient and sustainable approach for the synthesis of amine-containing compounds through C-H amination. A quantum chemical study reveals that nitrene formation is the rate-determining step in the overall reaction, and the catalyst with a serine ligand exhibits the highest reactivity.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Yongdi Wu, Na Liu, Meifang Qi, Huihao Qiao, Xuelian Lu, Li Ma, Yirong Zhou, Fang-Lin Zhang
Summary: 2-Fluoro-5-(trifluoromethyl)aniline is a suitable MonoTDG for enabling Ru(II)-catalyzed ortho-C(sp(2))-H imidation of benzaldehydes. N-Tosyloxyphthalimide serves as an alternative amidation reagent, allowing for high efficiency and good functional group tolerance. The reaction can be scaled up to gram scale and the amidated product can be easily converted into valuable scaffolds with one-step derivatization.
Article
Chemistry, Physical
Hyejin Kwon, Carson J. Bruns
Summary: Researchers have discovered and characterized a family of all-hydrocarbon, all-p-conjugated [n]cycloparaphenylene-PAH host-guest complexes. They have built a theoretical framework to select these complexes and predict their stabilities. This research offers new opportunities for bespoke PAH separation or remediation materials.
Article
Chemistry, Physical
J. Pablo Martinez, Bartosz Trzaskowski
Summary: In this study, we investigated the stereoselectivity of cross metathesis reaction using computational methods and obtained results consistent with experimental observations. The evaluation of structural strain provided insights into the design of stereoselective catalysts.
CATALYSIS COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Parvin Safari, Simon Gueckel, Josef B. G. Gluyas, Stephen A. Moggach, Martin Kaupp, Paul J. Low
Summary: The electronic structure and spectroscopic properties of ligand-bridged, bimetallic 'mixed-valence' complexes are determined by electronic couplings and orbital overlaps between the metal centers. The population distribution and dominant electronic structure can be biased by the steric and electronic properties of the bridge.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Lirong Lin, Denis M. Spasyuk, Roger A. Lalancette, Demyan E. Prokopchuk
Summary: The weakening of C-H bonds when interacting with transition metals was studied. By using a nickel complex and a robust adamantyl reporter ligand, the acidity and bond dissociation free energy of C-H bonds were measured, revealing a significant decrease in acidity and bond dissociation free energy upon coordination.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Kai Oberdorf, Patrick Grenzer, Nele Wieprecht, Jacqueline Ramler, Anna Hanft, Anna Rempel, Andreas Stoy, Krzysztof Radacki, Crispin Lichtenberg
Summary: The cationization of Bi(NPh2)(3) for single- and double-CH activation reactions has been successfully applied to bismuth amides with two aryl groups at the nitrogen, resulting in the first example of a homoleptic bismuth amide with a mixed aryl/alkyl substitution pattern. The Lewis acidity of neutral bismuth amides was compared with that of cationic species using the Gutmann-Beckett method. The heteroaromatic character of [Bi(C6H3R)(2)NH(triflate)] compounds was investigated by theoretical methods, revealing their iso-valence-electronic nature with anthracene.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Damien Mahaut, Aurelien Chardon, Loic Mineur, Guillaume Berionni, Benoit Champagne
Summary: The article demonstrates the activation of methane using 1-aza-9-boratriptycene as an intramolecular frustrated Lewis pair (FLP) through density functional theory (DFT) analysis. The study shows that the nature of the Lewis base influences the selectivity over the reaction pathway, with N Lewis bases favoring the deprotonation mechanism and P bases the hydride abstraction one.
Article
Chemistry, Physical
Min Zhang, Yang Wang, Shi-Jun Li, Xinghua Wang, Qianqian Shi, Xue Li, Ling-Bo Qu, Donghui Wei, Yu Lan
Summary: This study proposes an NHC and NHC center dot H+ cooperative catalytic model for inert C-C bond activations, and uses density functional theory calculations to discover two ways in which the organocatalyst functions in [4 + 2] annulation reactions. It also introduces an atomic electronegativity index to predict the site of stereoselective C-C bond formation accurately.
Article
Chemistry, Organic
Ling Meng, Heyang Liu, Zhenyang Lin, Jun Wang
Summary: Highly efficient and straightforward access to enantioenriched five-membered ring-fused chromanones is achieved via [3+2]-cycloaddition. The reaction yields densely functionalized chiral cyclopenta[b]chromanones with high enantioselectivity and diastereoselectivity. The mechanism and selectivity of the reaction have been investigated.
Article
Chemistry, Multidisciplinary
Tong-Tong Liu, Jiaxin Chen, Xin-Lei Chen, Li Ma, Bing-Tao Guan, Zhenyang Lin, Zhang-Jie Shi
Summary: A new class of boryl radicals ligated by a cyclic CAAC is reported, featuring a large spin density on the boron center as ascertained by EPR spectroscopy and DFT calculations. Structural and computational analyses revealed that stability of these radicals is assisted by the CAAC ligand and a weak but significant B(III)Br-B(II) interaction, suggesting a cooperative avenue for stabilization of boryl radicals. Two-electron reduction of these radicals provides C-H insertion products via a borylene intermediate.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Tong-Tong Liu, Jiaxin Chen, Bing-Tao Guan, Zhenyang Lin, Zhang-Jie Shi
Summary: Derived from structurally similar precursors, two different azidodiboranes underwent distinct aryl migration reactions triggered by different boron-boron separation distances. A shorter boron-boron distance led to heterolateral aryl migration and the formation of a seven-membered azadiborepin, while a longer boron-boron distance resulted in a stable bis-azidoborane scaffold. The pyrolysis of the bis-azidoborane led to the formation of an eight-membered oxazadiborocine through homolateral aryl migration and subsequent [3+2] cycloaddition. Density functional theory (DFT) calculations revealed that the boron-boron separation distances were the intrinsic factors driving the distinct migrations.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Wing Hei Marco Wong, Xueying Guo, Hok Tsun Chan, Tilong Yang, Zhenyang Lin
Summary: Heavier main-group element-catalyzed reactions have become an increasingly attractive tool for mimicking the behaviors of transition metal catalysts. The Bi-catalyzed synthesis of aryl sulfonyl fluorides reported by Magre and Cornella exhibits the ability of hypervalent coordination of the Bi(III) center and the high polarity of the Bi-Ph bond, allowing the heavier main-group element to resemble the transition metal in ligand association and dissociation flexibility. Additionally, the migrating Ph group's available pi electron pair stabilizes the SO2 insertion transition state by maintaining interaction with the Bi(III) center during migration.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Xin Xu, Zhenyang Lin
Summary: A mild synthetic method for transforming aromatic carbon-oxygen (C-O) bonds into useful molecules was reported. The method involved the use of a carbene complex to catalyze the asymmetric ring-opening reaction of dinaphthofuran with PhMgCl at room temperature. Density functional theory (DFT) calculations were performed to investigate the detailed mechanism, revealing a novel pathway involving Mg(II)-O coordination, phenyl nucleophile migration, and oxidative addition of a C-O bond to Ni(0). Insights into the role of the chiral NHC ligand in inducing enantioselectivity were also obtained.
Article
Chemistry, Multidisciplinary
Junyi Wang, Shuai Zhu, Wangyang Ma, Zhenyang Lin, Qing Ye
Summary: BN-butafulvenes, mono-BN isosteres of butafulvene and highly strained isomers of azaborines and B-amino boroles, have been synthesized via hydrolysis of the urana-borabicyclic complexes obtained from the reactions of bis(alkynyl)boranes with an uranacyclopropene complex. Their 4-dimethylaminopyridine (DMAP) adducts can further isomerize to 1,2,4,6-multisubstituted BN-9,1-naphthalenes. Both NMR reaction monitoring and theoretical calculations point to a reaction mechanism involving dearomative insertion of DMAP followed by two consecutive 1,2-hydrogen shifts. The photophysical studies of the highly substituted BN-9,1-naphthalenes reveal a notable redshift in both the UV/Vis absorption and emission spectra. The (TD)-DFT calculations corroborate the experimental data, suggesting that the strong pi-donating amino substitution at the 1- and/or 6-positions destabilizes the HOMO, and thus leading to a notable decrease of the HOMO-LUMO gap.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Shuxuan Liu, Ka Lok Chan, Zhenyang Lin, Jianwei Sun
Summary: This article reports the use of extended quinone methides with carbonyl and methide units distributed across two different rings as intermediates for asymmetric synthesis. By using suitable chiral phosphoric acids, the first asymmetric process involving such intermediates was achieved. These processes provide a rapid and highly enantioselective access to previously less accessible remotely chiral naphthols and naphthylamines. Control experiments and DFT calculations reveal important insights into the reaction mechanism, which likely involves the role of two phosphoric acid molecules in the enantiodetermining transition states. This work serves as a proof of concept for the exploitation of new types of extended quinone methides as versatile intermediates for asymmetric synthesis, offering a new platform for the efficient construction of remote benzylic stereogenic centers of aromatic compounds.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Kalok Chan, Long Thanh Ta, Yong Huang, Haibin Su, Zhenyang Lin
Summary: In this study, a simple molecular representation method was developed using machine learning and artificial intelligence techniques to predict rate constants of aryl bromides in palladium-catalyzed Sonogashira coupling reactions. The results demonstrate the importance of incorporating domain knowledge into machine learning for improved data analysis.
Article
Chemistry, Multidisciplinary
Xiaonan Li, Tilong Yang, Jiayuan Li, Xiang Li, Pinhong Chen, Zhenyang Lin, Guosheng Liu
Summary: Palladium-catalyzed remote 1,n-dioxygenation (n = 4) of internal alkenes using engineered pyridine-oxazoline (Pyox) ligands is reported. The reactions exhibit high regio- and enantioselectivity, and have a broad substrate scope, providing optically pure 1,n-diol acetates as key synthons for bioactive molecules. Experimental and theoretical studies reveal that the regioselectivity is controlled by the reactivity disparity of two allylic C-H bonds, with the first palladium migration step being the regioselectivity-determining step facilitated by modified phenyl-substituted Pyox ligands.
Article
Chemistry, Inorganic & Nuclear
Rain Ng, Shun-Cheung Cheng, Ka-Lok Chan, Cheuk-Pui Leung, Wai-Man Cheung, Herman H. -Y. Sung, Hung Kay Lee, Chi-Chiu Ko, Ian D. Williams, Zhenyang Lin, Wa-Hung Leung
Summary: In this study, iridium complexes containing a bis-cyclometalated tripodal CANAC ligand were synthesized and their redox property and reactivity were investigated. Various iridium complexes were successfully obtained through different reactions, and their structures and properties were further studied. The results highlighted the crucial role of the CANAC ligand in stabilizing high-valent iridium.
Article
Chemistry, Multidisciplinary
Masahiro Yamamoto, Wing Chun Chan, Zhenyang Lin, Makoto Yamashita
Summary: The reaction between tetra(o-tolyl)diborane(4) and organic azides yields three different compounds, diborylamines, diboryltriazenes, and B-2-hexazenes with a bicyclic B2N6 ring system. Aryl azides react to form diborylamines, while 1 equiv. of alkyl azides results in diboryltriazenes. Excess primary alkyl azide leads to the formation of new heterocyclic B-2-hexazenes. Control experiments and DFT calculations support the general reaction mechanism via diboryltriazenes to explain the formation of the B2N6 structure. The B-2-hexazenes exhibit strong fluorescence with a high fluorescent quantum yield of up to 96%.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Wenlong Sun, Chi-Ming Au, Ka-Wa Wong, Ka Lok Chan, Cheuk Kit Ngai, Hung Kay Lee, Zhenyang Lin, Wing-Yiu Yu
Summary: Directarene C-H functionalization by amidyl radicals has made significant progress for arylamides synthesis. Photocatalytic protocols can easily generate amidyl radicals under mild conditions, but designing catalysts with earth-abundant Fe complexes for C-H amidation is an attractive approach for controlling selectivity. However, the preference for high-spin configuration makes it challenging to design robust Fe catalysts for C-H amidation.
Article
Chemistry, Physical
Yongheng Jia, Ruichen Li, Yang Zhou, Shenghe Zhao, Hui Yu, Jianpu Wang, Zhenyang Lin, Haibin Su, Ni Zhao
Summary: Perovskite light-emitting diodes (PeLEDs) based on 3D mixed Br-Cl compositions exhibit good color stability and efficiency in the sky-blue range, but suffer from a significant performance decay in the deep-blue emission. This decay is mainly attributed to the poor morphology of the emissive layer. By combining theoretical and experimental approaches, it is discovered that the exchange of halide ions in lead complexes drives the precipitation of CsCl, resulting in low solubility at high Cl/Br ratios and inadequate perovskite film coverage. A metastable dissolution strategy is proposed, leading to deep-blue PeLEDs with a record high EQE of 4% and excellent spectral stability.
Article
Chemistry, Multidisciplinary
Zhongming Cheng, Tilong Yang, Can Li, Yunshun Deng, Fangjia Zhang, Pinhong Chen, Zhenyang Lin, Shengming Ma, Guosheng Liu
Summary: This study presents a copper-catalyzed radical relay strategy for the site-selective cyanation of sp(2) C-H bonds in allenes. The reactions show broad substrate scope and remarkable functional group compatibility under mild conditions. The site-selectivity is attributed to the unique pocket created by the Cu-bound nitrogen-centered radical and the crucial hydrogen bonding between the fluoride and the hydrogen atom. Late-stage functionalization of drug-like bioactive molecules containing an allene motif becomes feasible.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Jiao Jiao, Pei He, Tilong Yang, Tingwei Zhang, Linghua Wang, Tian Han, Yong Nie, Zhenyang Lin, Pengfei Li
Summary: An asymmetric synthesis of chiral metallacarboranes using a traceless chiral N-tertbutylsulfinamide auxiliary is reported. Investigations reveal a stereospecific SN2-type reaction mechanism, providing a new pathway for the preparation of chiral metallacarboranes and related compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
