Article
Chemistry, Multidisciplinary
Shubhajit Das, Ruben Laplaza, J. Terence Blaskovits, Clemence Corminboeuf
Summary: This study reveals that spatial constraints imposed on molecular catalysts can be utilized as a handle to enhance intrinsic activity in bifunctional catalysis. By controlling the geometry of the active site, the catalytic activity of frustrated Lewis pairs (FLPs) in the hydrogenation of CO2 can be greatly increased. This can be achieved by fixing the donor-acceptor centers at specific distances and orientations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Laura Koering, Nikolai A. Sitte, Jan Paradies
Summary: The paper reviews the development of frustrated Lewis pair catalyzed hydrogenation of tertiary and secondary amides, as well as strategies to overcome challenges in the reaction development process. Furthermore, the chemistry is extended to the hydrogenation of polyamides and trifluoroacetamides for the introduction of trifluoroethyl groups into organic molecules.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Laura Koering, Nikolai A. Sitte, Markus Bursch, Stefan Grimme, Jan Paradies
Summary: The metal-free catalytic hydrogenation of secondary carboxylic acid amides is achieved through two new catalytic reactions, involving the conversion of amides into imidoyl chlorides and the subsequent hydrogenation of the generated chlorides by an FLP-catalyst. Mechanistic and quantum mechanical calculations support the unique role of chloride as a Lewis base in FLP-mediated H-2-activation during the hydrogenation process.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Damien Mahaut, Benoit Champagne, Guillaume Berionni
Summary: In this study, frustrated Lewis pairs were used as catalysts for the hydrogenation of unactivated alkenes with H-2. Ortho-substituted 9-phosphatriptycene derivatives, with weak Lewis basicity and high steric hindrance, were found to be advantageous in catalyzing this reaction in combination with tris(pentafluorophenyl)borane. The protonation of the olefin by the strongly acidic phosphonium cation was identified as the critical step in the reaction.
Article
Chemistry, Multidisciplinary
Tongtong Wang, Maotong Xu, Andrew R. Jupp, Shi-Ming Chen, Zheng-Wang Qu, Stefan Grimme, Douglas W. Stephan
Summary: In the presence of 10 mol% B(2,6-C6F2H3)(3), excess tetramethylpiperidine (TMP) and H-2 (or D-2), catalytic hydrogenative dehalogenation of benzyl-halides to yield corresponding toluene derivatives is achieved. This reaction proceeds through the initial FLP activation of H-2 to form ammonium hydridoborate [TMPH][HB(2,6-C6F2H3)(3)], which then cooperatively activates the C-X bond (X = Cl, Br, I) of benzyl-halides to generate the corresponding ammonium halide salts.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Shubhajit Das, Roland C. Turnell-Ritson, Paul J. Dyson, Clemence Corminboeuf
Summary: Despite recent progress in the chemistry of frustrated Lewis pairs (FLPs), direct FLP-catalyzed hydrogenation of CO2 remains elusive. The authors propose a mapping method to link the chemical composition of FLPs with their activity in catalytic hydrogenation of CO2, and they experimentally validate a combination with high catalytic turnover.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Joshua S. Sapsford, Daniel Csokas, Roland C. Turnell-Ritson, Liam A. Parkin, Andrew D. Crawford, Imre Papai, Andrew E. Ashley
Summary: The newly synthesized compound iPr(3)SnNTf(2) exhibits stronger Lewis acid properties compared to previously studied compounds, enabling faster hydrogen activation and catalytic hydrolysis of ester bonds. The reaction outcome is influenced by the steric and electronic properties of the substrate, with computational studies revealing differences in the reaction mechanisms between different ester substrates.
Article
Chemistry, Multidisciplinary
Xinyue Tan, Huadong Wang
Summary: The concept of frustrated Lewis pair (FLP) chemistry has become a rich and fruitful research area, contributing significantly to the revival of main group chemistry. The design of catalytic systems based on the FLP concept has been successfully applied to organic synthesis and polymer chemistry.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Tongtong Wang, Maotong Xu, Andrew R. Jupp, Zheng-Wang Qu, Stefan Grimme, Douglas W. Stephan
Summary: The frustrated Lewis pair (FLP) derived from 2,6-lutidine and B(C6F5)(3) has been shown to mediate the catalytic hydrogenation of CO2, with control over product nature through careful selection of silylhalide and solvent. This metal-free catalysis offers pathways to selectively form specific compounds under mild conditions, as elucidated by DFT studies on the mechanism and selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Benedikt Sieland, Axel Hoppe, Arne J. Stepen, Jan Paradies
Summary: A frustrated Lewis pair-catalyzed hydroboration of aromatic and aliphatic nitriles was developed, providing primary amines in high yields with low catalyst loading. The reaction exhibits high functional group tolerance and Z-selectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Physical
Haishuai Cui, Linhao Zhong, Xiaoqing Liao, Fang Hao, Wei Xiong, Huajie Liu, Hean Luo, Pingle Liu, Yang Lv
Summary: Zeolitic imidazolate frameworks (ZIFs) were prepared through different methods for the chemoselective hydrogenation of biomass-derived cinnamaldehyde. Defective ZIFs prepared by microwave-assisted method (ZIF-67-MW) exhibited more defects, which led to the formation of a heterogeneous Frustrated Lewis pairs (FLPs) system with independent Lewis acid and Lewis basic sites. Theoretical calculations showed that the FLPs sites in the defective ZIFs had low activation energy for dissociating the H-H bond. A silica-coated and hydrophobically modified core-shell structure (ZIF-67-MW@SiO2-DMDES) was developed to enhance stability and selectivity, achieving high conversion of cinnamaldehyde to cinnamyl alcohol. Substrate-extending experiments demonstrated that ZIF-67-MW@SiO2-DMDES had promising potential in the selective hydrogenation of various unsaturated aldehydes.
JOURNAL OF CATALYSIS
(2023)
Article
Engineering, Environmental
Zhaowei Tian, Lei Wang, Tianyao Shen, Pan Yin, Weimin Da, Zhitong Qian, Xun Zhao, Guirong Wang, Yusen Yang, Min Wei
Summary: A synthesis approach for solid frustrated Lewis pairs (FLPs) has been developed, and the spatial hindrance in generating various FLP sites has been demonstrated. Depending on the catalyst, different selectivities in hydrogenation reactions can be achieved. The structure-property relationship based on in situ spectroscopy and density functional theory calculations provides new insights for the development of selective heterogeneous hydrogenation reactions catalyzed by solid FLPs.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Wenhao Yu, Yanyun Zhang, Yingnan Qin, Dan Zhang, Kang Liu, G. A. Bagliuk, Jianping Lai, Lei Wang
Summary: This study presents a method to construct catalysts with regulable acidity and basicity by utilizing the Mott-Schottky effect on an intermetallic alloy. The developed fct-PtCo@NC catalyst with high-density frustrated Lewis pair (FLP) sites shows outstanding performance in the hydrogen evolution reaction. The synergistic effect of FLP-acid sites and FLP-base sites significantly reduces the energy barrier between water adsorption and decomposition, resulting in faster reaction kinetics.
ADVANCED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Matthew E. Grundy, Lia Sotorrios, Milan Kumar Bisai, Kang Yuan, Stuart A. Macgregor, Michael J. Ingleson
Summary: [(NacNac)Zn(DMT)][B(C6F5)4], 1, was synthesized and demonstrated as an efficient catalyst for the C-H borylation of (hetero)arenes using catecholborane. Computational studies revealed a plausible mechanism involving displacement of DMT by CatBH and subsequent steps including dehydrocoupling and displacement of CatBAr. The research also provided insight into a possible decomposition pathway of the catalyst involving boron to zinc hydride transfer.
Article
Chemistry, Physical
Matthew E. Grundy, Lia Sotorrios, Milan Kumar Bisai, Kang Yuan, Stuart A. Macgregor, Michael J. Ingleson
Summary: This article reports the synthesis of (NacNac)Zn(DMT) complex via two different routes and its use as a catalyst for C-H borylation. Computational studies elucidated the reaction mechanism and revealed the influence of the electronic and steric parameters of the base on the catalyst's performance.
Article
Chemistry, Multidisciplinary
Julia Kohn, Markus Bursch, Andreas Hansen, Stefan Grimme
Summary: This study investigates the structural properties of mu(2)-bridged porphyrinic double-decker complexes and elucidates the influence of various ligands, metals, substituents, and bridging atoms on the dominant structural motif. The use of different quantum chemical methods and analysis tools provides reliable calculations and insights into the bonding situation and inter-ligand interaction energy.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Wenxing Zou, Markus Bursch, Kristian L. Mears, Cary R. Stennett, Ping Yu, James C. Fettinger, Stefan Grimme, Philip P. Power
Summary: The reaction between {LiC6H2-2,4,6-Cyp(3).Et2O}(2) and SnCl2 generates a mixture of {Sn(C6H2-2,4,6-Cyp(3))(2)}(2) and {Sn(C6H2-2,4,6-Cyp(3))(2)}(3). The equilibrium between 2 and 3 is influenced by temperature and the conversion of 3 to 2 is an endergonic process. Computational studies reveal that dispersion interactions play a crucial role in determining the stability of 3 and 2, with 3 being more stable due to higher DED stabilization energy.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Benedikt Wolff, Zheng-Wang Qu, Stefan Grimme, Martin Oestreich
Summary: This study presents a method for the enantioselective reduction of simple carbenium ions using cyclohexadienes with a hydridic C-H bond at an asymmetrically substituted carbon atom. Chiral cyclohexadienes are used as dihydrogen surrogates for the transfer hydrogenation of alkenes (styrenes). The reaction mechanism involves the initiation by trityl cation and a delicate intermolecular capture of a carbenium-ion intermediate by the chiral hydride source, resulting in good enantiomeric ratios of the reduction products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Julia T. Kohn, Hong Li, Austin M. Evans, Jean-Luc Bredas, Stefan Grimme
Summary: 2D covalent organic frameworks (COFs) possess desirable mechanical and optoelectronic properties, but experimental structure determination remains challenging due to inseparable isomers and limited computational models. In this study, we go beyond the conventional description of COF building blocks and investigate the impact of different stacking and structural motifs on electronic properties. Using the SQM GFN-xTB method, we analyze the structural, energetic, electronic, and spectroscopic results of an imine-linked COF and compare them to experimental findings.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Stefan Grimme, Marcel Mueller, Andreas Hansen
Summary: This article describes a new tight-binding electronic structure Hamiltonian that achieves high accuracy and speedup in calculations using a deeply contracted valence double-zeta basis set. The method performs well for difficult systems and bonding situations, and can be used for machine learning applications or as a basis for accurate high-speed DFT methods.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Marcel Bamberg, Thomas Gasevic, Michael Bolte, Alexander Virovets, Hans-Wolfram Lerner, Stefan Grimme, Markus Bursch, Matthias Wagner
Summary: Silafulleranes with endohedral Cl- ions are a unique class of silicon clusters and host-guest complexes. In this study, regioselective derivatization reactions were performed on a specific siladodecahedrane, resulting in the formation of perhydrogenated and non-pyrophoric hydridosilanes. The influence of solvent on the reaction outcomes was also investigated.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Benedikt Sieland, Marcel Stahn, Roland Schoch, Constantin Daniliuc, Sebastian Spicher, Stefan Grimme, Andreas Hansen, Jan Paradies
Summary: An isostructural series of boron/phosphorus Lewis pairs were investigated systematically. The association constants of the Lewis pairs were determined and thermodynamic parameters were extracted at different temperatures. The stabilization of the Lewis adduct increased with the size of the dispersion energy donor groups, despite the donor and acceptor properties of the Lewis pairs remaining largely unchanged. This data was used to challenge state-of-the-art quantum chemical methods and resulted in an enhanced workflow for accurately determining the thermochemical properties of weakly bound Lewis pairs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Daniel Kalle, Joshua Bahr, Tristan Johannes Keller, Julius B. Kleine Buening, Stefan Grimme, Markus Bursch, Stefan-Sven Jester, Sigurd Hoeger
Summary: The modular synthesis of nanoscale phenylene bicyclophanes with an intraannular orthogonal pillar is described in this study. The compounds were characterized by various analytical techniques, and their structures and conformations were further supported by quantum chemical calculations. It was found that the number of alkyl chains per molecule plays a crucial role in determining the structural stability of the assembled molecules on graphite. This study provides important insights into the assembly and characterization of nanomaterials.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
J. T. Kohn, N. Gildemeister, S. Grimme, D. Fazzi, A. Hansen
Summary: Designing organic semiconductors for practical applications requires understanding charge transfer mechanisms. This study used a semiempirical quantum mechanical method combined with a non-self-consistent density matrix tight-binding potential to evaluate charge transfer integrals. The results showed that the method consistently performs well for calculating coupling integrals with reasonable accuracy at low computational cost.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Hagen Neugebauer, Benedikt Badorf, Sebastian Ehlert, Andreas Hansen, Stefan Grimme
Summary: The semiempirical GFNn-xTB methods are extended with spin-polarization to efficiently screen different spin states of transition metal complexes. The new spGFNn-xTB methods overcome the limitation of properly distinguishing between high-spin and low-spin states. Performance evaluation on a benchmark set of 90 complexes shows that spGFNn-xTB methods yield the lowest mean absolute deviation (MAD) for spin state energy splittings.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Dipendu Mandal, Zheng-Wang Qu, Stefan Grimme, Douglas W. Stephan
Summary: Cyclopropenium cations with electron deficient substituents exhibit Lewis acidity despite the presence of π-electrons. The chloride and electron affinities are analyzed computationally and experimentally, respectively. These cations form traditional Lewis acid-base adducts with PPh3, while sterically hindered phosphines lead to frustrated Lewis pairs that participate in FLP additions. Depending on the basicity of the phosphine, addition to alkynes or alkyne deprotonation can occur. In both cases, new C-C bonds are formed, thus expanding the application of FLP chemistry to these delocalized π-cations.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Christoph Plett, Abylay Katbashev, Sebastian Ehlert, Stefan Grimme, Markus Bursch
Summary: Efficient quantum chemical methods are required for the computational treatment of large molecular structures. The ONIOM multi-layer scheme has been successfully implemented into the xtb program package and applied to transition-metal complexes with hundreds of atoms. By combining density functional theory, semi-empirical, and force-field methods in the ONIOM framework, computational costs can be significantly reduced without sacrificing accuracy.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Marcel Bamberg, Thomas Gasevic, Michael Bolte, Alexander Virovets, Hans-Wolfram Lerner, Stefan Grimme, Markus Bursch, Matthias Wagner
Summary: Treating perhydrogenated silafullerane [nBu(4)N][Cl@Si-20(SiH3)(12)H-8] with BBr3 resulted in partially and exhaustively brominated clusters, [nBu(4)N][Cl@Si-20(SiBr2H)(12)Br-8] and [nBu(4)N][Cl@Si-20(SiBr3)(12)Br-8], respectively. Full bromination increased steric strain on the cluster surface, enabling regioselective derivatization of the Si-32 framework under mild conditions. Partial Br/H exchange on [nBu(4)N][Cl@Si-20(SiBr2H)(12)Br-8] with iBu(2)AlH yielded [nBu(4)N][Cl@Si-20(SiH3)(12)Br-8].
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Vaibhav Bedi, Dipendu Mandal, Zahid Hussain, Shi-Ming Chen, Yile Wu, Zheng-Wang Qu, Stefan Grimme, Douglas W. Stephan
Summary: The reaction of (tBuO(2)CN)(2) with 9-BBN leads to the formation of a bicyclic heterocyclic compound, while its reactions with BF3 or [Et3Si][B(C6F5)(4)] result in the isolation of different compounds. Computational studies reveal that the steric and electronic properties of the Lewis acid are important in the formation of one of the compounds.
DALTON TRANSACTIONS
(2024)
