1
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Csókás D, Coles M, Toh ZH, Young RD. Evidence for a kinetic FLP reaction pathway in the activation of benzyl chlorides by alkali metal-phosphine pairs. Dalton Trans 2024; 53:14582-14586. [PMID: 39162088 DOI: 10.1039/d4dt02028f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/21/2024]
Abstract
Kinetic frustrated Lewis pairs (FLP) allow facile cleavage of a number of E-H bonds (E = H, Si, C, B) where both the Lewis base and Lewis acid are involved in the bond activation transition state. More recently, kinetic FLP systems have been extended to the cleavage of C-X (X = F, Cl, Br) bonds. We report on the role of sodium tetrakis(pentafluorophenyl)borate in the benzylation of triarylphosphines, where the sodium cation and phosphine support a kinetic FLP type transition state.
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Affiliation(s)
- Dániel Csókás
- Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, H-1117 Budapest, Hungary
| | - Max Coles
- School of Chemistry and Molecular Biosciences, University of Queensland, 68 Cooper Road, Australia 4067.
| | - Zhi Hao Toh
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Rowan D Young
- School of Chemistry and Molecular Biosciences, University of Queensland, 68 Cooper Road, Australia 4067.
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2
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Barrales-Martínez C, Illanes-Solis C, Durán R, Caballero J. Exploring the electronic and steric effects on the dimerization of intramolecular frustrated Lewis pairs: a comparison between aminoboranes and aminoalanes. Dalton Trans 2024; 53:7000-7011. [PMID: 38563207 DOI: 10.1039/d3dt04274j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The dimerization of intramolecular aminoborane and aminoalane frustrated Lewis pairs was investigated using density functional theory. We systematically varied the substituents to gradually increase their bulkiness, including H, CH3, t-Bu, Ph, and Mes groups. Starting from the most stable conformer of the monomers, a frustrated Lewis pair or classic Lewis adduct, we studied the dimerization process for all systems, revealing significant variations in the Gibbs free energy. Dimerization was favored in four aminoboranes and six aminoalanes, depending on the specific combinations of substituents. Applying an energy decomposition analysis, we found that the preparation energy of the monomers and the non-orbital interactions between them are the primary contributors to the observed energetic differences, showing a clear linear relationship. Additionally, we analyzed the electronic effects by increasing the acidity of the Lewis acid, observing a shift toward endergonic and exergonic directions in aminoboranes and aminoalanes, respectively. This shift was attributed to the stabilization of a classic Lewis adduct. This study underscores three crucial factors influencing dimer formation: (i) substituent size, (ii) stabilization of the classic Lewis adduct conformation, and (iii) covalent radii of the Lewis centers. Understanding these factors is essential for designing FLPs and preventing unwanted dimerization that could affect their catalytic performance in H2 activation processes.
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Affiliation(s)
- César Barrales-Martínez
- Instituto de Investigación Interdisciplinaria (I3), Vicerrectoría Académica, Universidad de Talca, Campus Talca, Talca, Chile.
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, Campus Talca, Talca, Chile
| | - Claudio Illanes-Solis
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, Campus Talca, Talca, Chile
| | - Rocío Durán
- Instituto de Investigación Interdisciplinaria (I3), Vicerrectoría Académica, Universidad de Talca, Campus Talca, Talca, Chile.
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, Campus Talca, Talca, Chile
| | - Julio Caballero
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, Campus Talca, Talca, Chile
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3
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Frenette BL, Rivard E. Frustrated Lewis Pair Chelation in the p-Block. Chemistry 2023; 29:e202302332. [PMID: 37677126 DOI: 10.1002/chem.202302332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 09/09/2023]
Abstract
Frustrated Lewis pairs (FLPs) have been the subject of considerable study since the field's inception. While much of the research into FLPs has centered around small molecule activation for diverse stoichiometric and catalytic transformations, intramolecular FLPs also show promise as chelating ligands. The cooperative action of Lewis basic and acidic moieties enables intramolecular FLPs to stabilize low oxidation state centers and (consequently) reactive molecular fragments through a donor-acceptor approach, making them an attractive ligand class in main group element chemistry. This review outlines the state of FLP chelation to date throughout the p-block, encompassing primarily groups 13-16.
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Affiliation(s)
- Brandon L Frenette
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada
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4
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Barrales-Martínez C, Durán R, Jaque P. New insights into H 2 activation by intramolecular frustrated Lewis pairs based on aminoboranes: the local electrophilicity index of boron as a suitable indicator to tune the reversibility of the process. Chem Sci 2023; 14:11798-11808. [PMID: 37920343 PMCID: PMC10619628 DOI: 10.1039/d3sc03992g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/03/2023] [Indexed: 11/04/2023] Open
Abstract
A large set of intramolecular aminoborane-based FLPs was studied employing density functional theory in the H2 activation process to analyze how the acidity and basicity of boron and nitrogen atoms, respectively, affect the reversibility of the process. Three different linkers were employed, keeping the C-C nature in the connection between both Lewis centers: -CH2-CH2-, -CH[double bond, length as m-dash]CH-, and -C6H4-. The results show that significant differences in the Gibbs free energy of the process are found by considering all the combinations of substituents. Of the 75 systems studied, only 9 showed the ability to carry out the process reversibly (ΔGH2 in the range of -3.5 to 2.0 kcal mol-1), where combinations of alkyl/aryl or aryl/alkyl in boron/nitrogen generate systems capable of reaching reversibility. If the alkyl/alkyl or aryl/aryl combination is employed, highly exergonic (non-reversible H2 activation) and endergonic (unfeasible H2 activation) reactions are found, respectively. No appreciable differences in the linker were found, allowing us to continue the analysis with the most entropically favorable linker, the -C6H4- linker. From this, 25 different FLP systems of type 2-[bis(X)boryl]-(Y)aniline (X: H, CF3, C6F5, PFtB, FMes and Y: H, CH3, t-but, Ph, Mes) can be formed. By analyzing the electronic properties of each system, we have found that the condensed-to-boron electrophilicity index ωB+ is inversely related to the ΔGH2. Interestingly, two relationships were found; the first is for alkyl groups (Y: CH3 and t-but) and the second for aryl groups (Y: H, Ph, and Mes), which is intimately related to the proton affinity of each aniline. In addition, it is quite interesting when the frustration degree, given by B⋯N distance dB-N, is brought together with ωB+, since the quotient has unit energy/length corresponding to unit force; concomitantly, a measure of the FLP strength in H-H bond activation can be defined. With this finding, a rational design of this kind of FLP can be performed by analyzing the acidity of boron through condensed-to-boron electrophilicity and knowing the nature of the substituent of nitrogen according to whether the Y is alkyl or aryl, optimizing the H2 reversible activation in a rational way, which is crucial to improve the catalytic performance.
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Affiliation(s)
- César Barrales-Martínez
- Instituto de Investigación Interdisciplinaria (I3), Vicerrectoría Académica and Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca Campus Lircay Talca 3460000 Chile
| | - Rocío Durán
- Instituto de Investigación Interdisciplinaria (I3), Vicerrectoría Académica and Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca Campus Lircay Talca 3460000 Chile
| | - Pablo Jaque
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile Sergio Livingstone 1007, Independencia Santiago Chile
- Centro de Modelamiento Molecular, Biofísica y Bioinformática, CM2B2, Universidad de Chile Sergio Livingstone 1007, Independencia Santiago Chile
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5
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Wickemeyer L, Schwabedissen J, Trapp PC, Neumann B, Stammler HG, Mitzel NW. ortho-Phenylene-bridged phosphorus/silicon Lewis pairs. Dalton Trans 2023; 52:2611-2618. [PMID: 36740914 DOI: 10.1039/d2dt04097b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A series of five ortho-phenylene-bridged phosphorus-silicon Lewis pairs was synthesized, with phosphorus bearing isopropyl groups while the substituents at the silicon atom vary (-CH3, -Cl, -F). Possible interactions between Lewis acid and base were investigated both experimentally (NMR, XRD) and theoretically to determine the influence of the different substituents. Calculated ortho-interaction energies (OIEs) show a stabilizing interactions between the acidic and basic units which were also found for the meta- and para-interaction energies (MIEs and PIEs, respectively), indicating stabilization resulting not from direct acid-base interaction but from electronic interactions through the ring. Further spectroscopic (NMR, XRD) and theoretical (NBO, QTAIM, SAPT) investigations confirmed the absence of direct interactions between silicon and phoshorus.
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Affiliation(s)
- Lucas Wickemeyer
- Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Jan Schwabedissen
- Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Pia C Trapp
- Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Beate Neumann
- Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Hans-Georg Stammler
- Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Norbert W Mitzel
- Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany.
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6
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Kannan R, Chandrasekhar V. Four-membered C^N chelation in main-group organometallic chemistry. Dalton Trans 2023; 52:1159-1176. [PMID: 36602433 DOI: 10.1039/d2dt03494h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Main-group organometallic compounds containing four-membered C^N chelating rings are being studied because of the interest in harnessing the enhanced reactivity of such compounds which arises as a result of the release of steric strain. In this article, we have reviewed the literature on these systems. This review is organised in terms of the types of ligand systems that allow the assembly of such compounds, viz., compounds containing aliphatic amine motifs, pyridine motifs and aniline motifs. In addition to a discussion on the synthesis and structure, we also examine the reactivity and applications of the main-group element compounds involved. In particular, applications involving H2 activation, carbonyl activation, olefin reduction, C-H activation, hydroalumination, cyanamide oligomerisation, borylation of olefins and heteroarenes, isocyanate activation and C-C bond activation are discussed.
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Affiliation(s)
- Ramkumar Kannan
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500 046, Telangana, India.
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500 046, Telangana, India. .,Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208 016, Uttar Pradesh, India
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7
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Sorochkina K, Chernichenko K, Zhivonitko VV, Nieger M, Repo T. Water Reduction and Dihydrogen Addition in Aqueous Conditions With ansa-Phosphinoborane. Chemistry 2022; 28:e202201927. [PMID: 35861909 PMCID: PMC9804508 DOI: 10.1002/chem.202201927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Indexed: 01/05/2023]
Abstract
Ortho-phenylene-bridged phosphinoborane (2,6-Cl2 Ph)2 B-C6 H4 -PCy2 1 was synthesized in three steps from commercially available starting materials. 1 reacts with H2 or H2 O under mild conditions to form corresponding zwitterionic phosphonium borates 1-H2 or 1-H2 O. NMR studies revealed both reactions to be remarkably reversible. Thus, when exposed to H2 , 1-H2 O partially converts to 1-H2 even in the presence of multiple equivalents of water in the solution. The addition of parahydrogen to 1 leads to nuclear spin hyperpolarization both in dry and hydrous solvents, confirming the dissociation of 1-H2 O to free 1. These observations were supported by computational studies indicating that the formation of 1-H2 and 1-H2 O from 1 are thermodynamically favored. Unexpectedly, 1-H2 O can release molecular hydrogen to form phosphine oxide 1-O. Kinetic, mechanistic, and computational (DFT) studies were used to elucidate the unique "umpolung" water reduction mechanism.
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Affiliation(s)
- Kristina Sorochkina
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio 100014HelsinkiFinland
| | - Konstantin Chernichenko
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio 100014HelsinkiFinland
- Chemical Process Research and Development Janssen PharmaceuticaTurnhoutseweg 302340BeerseBelgium
| | | | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio 100014HelsinkiFinland
| | - Timo Repo
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio 100014HelsinkiFinland
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8
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De los Santos ZA, Lynch CC, Wolf C. Dynamic Covalent Optical Chirality Sensing with a Sterically Encumbered Aminoborane. Chemistry 2022; 28:e202202028. [DOI: 10.1002/chem.202202028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Indexed: 11/07/2022]
Affiliation(s)
| | - Ciarán C. Lynch
- Department of Chemistry Georgetown University Washington DC 20057 USA
| | - Christian Wolf
- Department of Chemistry Georgetown University Washington DC 20057 USA
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9
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Carmona M, Pérez R, Ferrer J, Rodríguez R, Passarelli V, Lahoz FJ, García-Orduña P, Carmona D. Activation of H-H, HO-H, C(sp 2)-H, C(sp 3)-H, and RO-H Bonds by Transition-Metal Frustrated Lewis Pairs Based on M/N (M = Rh, Ir) Couples. Inorg Chem 2022; 61:13149-13164. [PMID: 35948430 PMCID: PMC9406284 DOI: 10.1021/acs.inorgchem.2c01902] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Reaction of the dimers [(Cp*MCl)2(μ-Cl)2] (Cp* = η5-C5Me5)
with Ph2PCH2CH2NC(NH(p-Tolyl))2 (H2L) in the presence
of NaSbF6 affords the chlorido complexes [Cp*MCl(κ2N,P-H2L)][SbF6] (M = Rh, 1; Ir, 2).
Upon treatment with aqueous NaOH, solutions of 1 and 2 yield the corresponding complexes [Cp*M(κ3N,N′,P-HL)][SbF6] (M = Rh, 3; Ir, 4) in which the ligand HL presents a fac κ3N,N′,P coordination mode. Treatment of THF solutions
of complexes 3 and 4 with hydrogen gas,
at room temperature, results in the formation of the metal hydrido-complexes
[Cp*MH(κ2N,P-H2L)][SbF6] (M = Rh, 5;
Ir, 6) in which the N(p-Tolyl) group
has been protonated. Complexes 3 and 4 react
with deuterated water in a reversible fashion resulting in the gradual
deuteration of the Cp* group. Heating at 383 K THF/H2O
solutions of the complexes 3 and 4 affords
the orthometalated complexes [Cp*M(κ3C,N,P-H2L-H)][SbF6] [M = Rh, 7; Ir, 8, H2L-H = Ph2PCH2CH2NC(NH(p-Tolyl))(NH(4-C6H3Me))], respectively. At 333 K, complexes 3 and 4 react in THF with methanol, primary alcohols,
or 2-propanol giving the metal-hydrido complexes 5 and 6, respectively. The reaction involves the acceptorless dehydrogenation
of the alcohols at a relatively low temperature, without the assistance
of an external base. The new complexes have been characterized by
the usual analytical and spectroscopic methods including the X-ray
diffraction determination of the crystal structures of complexes 1–5, 7, and 8. Notably, the chlorido complexes 1 and 2 crystallize both as enantiopure conglomerates and as racemates.
Reaction mechanisms are proposed based on stoichiometric reactions,
nuclear magnetic resonance studies, and X-ray crystallography as well
as density functional theory calculations. In solution, masked transition-metal
frustrated Lewis pairs
(TMFLPs) give rise to the corresponding TMFLP species which activate
dihydrogen, water, and alcohols following FLP reaction pathways. When
D2O or alcohols with deuterated OH groups were employed,
H/D exchange at the Cp* ligand (involving C(sp3)−H
activation) was observed. C(sp2)−H bond activation
involving orthometalation of the p-Tolyl ring was
also observed.
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Affiliation(s)
- María Carmona
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Roberto Pérez
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Joaquina Ferrer
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Ricardo Rodríguez
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Vincenzo Passarelli
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Fernando J Lahoz
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Pilar García-Orduña
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Daniel Carmona
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
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Schulz J, Sárosi MB, Hey‐Hawkins E. Exploring the Reactivity of B-Connected Carboranylphosphines in Frustrated Lewis Pair Chemistry: A New Frame for a Classic System. Chemistry 2022; 28:e202200531. [PMID: 35472172 PMCID: PMC9320892 DOI: 10.1002/chem.202200531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Indexed: 11/15/2022]
Abstract
The primary phosphines MesPH2 and tBuPH2 react with 9-iodo-m-carborane yielding B9-connected secondary carboranylphosphines 1,7-H2 C2 B10 H9 -9-PHR (R=2,4,6-Me3 C6 H2 (Mes; 1 a), tBu (1 b)). Addition of tris(pentafluorophenyl)borane (BCF) to 1 a, b resulted in the zwitterionic compounds 1,7-H2 C2 B10 H9 -9-PHR(p-C6 F4 )BF(C6 F5 )2 (2 a, b) through nucleophilic para substitution of a C6 F5 ring followed by fluoride transfer to boron. Further reaction with Me2 SiHCl prompted a H-F exchange yielding the zwitterionic compounds 1,7-H2 C2 B10 H9 -9-PHR(p-C6 F4 )BH(C6 F5 )2 (3 a, b). The reaction of 2 a, b with one equivalent of R'MgBr (R'=Me, Ph) gave the extremely water-sensitive frustrated Lewis pairs 1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 )B(C6 F5 )2 (4 a, b). Hydrolysis of the B-C6 F4 bond in 4 a, b gave the first tertiary B-carboranyl phosphines with three distinct substituents, 1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 H) (5 a, b). Deprotonation of the zwitterionic compounds 2 a, b and 3 a, b formed anionic phosphines [1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 )BX(C6 F5 )2 ]- [DMSOH]+ (R=Mes, X=F (6 a), R=tBu, X=F (6 b); R=Mes, X=H (7 a), R=tBu, X=H (7 b)). Reaction of 2 a, b with an excess of Grignard reagents resulted in the addition of R' at the boron atom yielding the anions [1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 )BR'(C6 F5 )2 ]- (R=Mes, R'=Me (8 a), R=tBu, R'=Me (8 b); R=Mes, R'=Ph (9 a), R=tBu, R'=Ph (9 b)) with [MgBr(Et2 O)n ]+ as counterion. The ability of the zwitterionic compounds 3 a, b to hydrogenate imines as well as the Brønsted acidity of 3 a were investigated.
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Affiliation(s)
- Jan Schulz
- Leipzig University, Faculty of Chemistry and Mineralogy Institute of Inorganic ChemistryJohannisallee 2904103LeipzigGermany
| | - Menyhárt B. Sárosi
- Leipzig University, Faculty of Chemistry and Mineralogy Wilhelm-Ostwald-Institute for Physical and Theoretical ChemistryLinnéstraße 204103LeipzigGermany
| | - Evamarie Hey‐Hawkins
- Leipzig University, Faculty of Chemistry and Mineralogy Institute of Inorganic ChemistryJohannisallee 2904103LeipzigGermany
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12
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Zhao Y, Chen Y, Zhang L, Li J, Peng Y, Chen Z, Jiang L, Zhu H. Homocoupling of Isocyanide at the Si(II) Center of Borylaminoamidinatosilylene. Inorg Chem 2022; 61:5215-5223. [PMID: 35312318 DOI: 10.1021/acs.inorgchem.1c03349] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Two borylaminoamidinatosilylenes (L)[(1,5-C8H14)B(Ar)N]Si (L = PhC(NtBu)2, Ar = 2,6-iPr2C6H3 (1)) and (L)[(1,5-C8H14)B(Ar')N]Si (Ar' = 2,4,6-Me3C6H2 (2)) have been prepared and utilized to investigate the reaction toward isocyanide. Reactions of 1 with the respective CN-2,6-Me2C6H3 and CNCy (Cy = cyclo-C6H11) produced compounds (L)Si(NAr)C(N-2,6-Me2C6H3)B(1,5-C8H14)(CN-2,6-Me2C6H3) (3) and (L)Si(NAr)C(NCy)C(NCy)B(1,5-C8H14)(CNCy) (4). Reactions of 2 with the respective CNCy and CN-2,6-Me2C6H3 yielded compounds cyclo-(L)SiN(Ar')C(NCy)B(1,5-C8H14)C(NCy) (5) and cyclo-(L)[(1,5-C8H14)B(Ar')N]SiC(CN-2,6-Me2C6H3)N(2,6-Me2C6H3)C(N-2,6-Me2C6H3) (6). Compounds 3-6 have different compositions and structures from each other. Density functional theory (DFT) calculations suggest initial formation of (L)[(1,5-C8H14)B(←:CN-2,6-Me2C6H3)(Ar)N]Si (A), (L)[(1,5-C8H14)B(←:CNCy)(Ar)N]Si (A'), (L)[(1,5-C8H14)B(←:CNCy)-(Ar')N]Si (A″), and (L)[(1,5-C8H14)B(←:CN-2,6-Me2C6H3)(Ar')N]Si (A‴) as the respective intermediates. The as-followed transition states TS, TS1', TS1″, and TS‴ all feature probable Si:→C(═N):→B bonding with different Gibbs energies of 7.24, 2.46, 3.86, and 6.59 kcal/mol, respectively, due to variation among the Ar, Ar', 2,6-Me2C6H3, and Cy groups in these species, and reacted in different ways.
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Affiliation(s)
- Yiling Zhao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yilin Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Li Zhang
- Center of Materials Science and Engineering, Guangxi University of Science and Technology, Liuzhou 545006, China
| | - Jiancheng Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yanbo Peng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Zhikang Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Liuyin Jiang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Hongping Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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Oishi T, Lugo-Fuentes LI, Jing Y, Jimenez-Halla JOC, Barroso-Flores J, Nakamoto M, Yamamoto Y, Tsunoji N, Shang R. Proton to hydride umpolung at a phosphonium center via electron relay: a new strategy for main-group based water reduction. Chem Sci 2021; 12:15603-15608. [PMID: 35003590 PMCID: PMC8654027 DOI: 10.1039/d1sc05135k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 11/13/2021] [Indexed: 11/21/2022] Open
Abstract
Generation of dihydrogen from water splitting, also known as water reduction, is a key process to access a sustainable hydrogen economy for energy production and usage. The key step is the selective reduction of a protic hydrogen to an accessible and reactive hydride, which has proven difficult at a p-block element. Although frustrated Lewis pair (FLP) chemistry is well known for water activation by heterolytic H-OH bond cleavage, to the best of our knowledge, there has been only one case showing water reduction by metal-free FLP systems to date, in which silylene (SiII) was used as the Lewis base. This work reports the molecular design and synthesis of an ortho-phenylene linked bisborane-functionalized phosphine, which reacts with water stoichiometrically to generate H2 and phosphine oxide quantitatively under ambient conditions. Computational investigations revealed an unprecedented multi-centered electron relay mechanism offered by the molecular framework, shuttling a pair of electrons from hydroxide (OH-) in water to the separated proton through a borane-phosphonium-borane path. This simple molecular design and its water reduction mechanism opens new avenues for this main-group chemistry in their growing roles in chemical transformations.
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Affiliation(s)
- Takumi Oishi
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima 739-8526 Japan
| | - Leonardo I Lugo-Fuentes
- Department of Chemistry, Division of Natural and Exact Sciences, University of Guanajuato, Campus Gto Noria Alta s/n 36050 Guanajuato Mexico
| | - Yichuan Jing
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima 739-8526 Japan
| | - J Oscar C Jimenez-Halla
- Department of Chemistry, Division of Natural and Exact Sciences, University of Guanajuato, Campus Gto Noria Alta s/n 36050 Guanajuato Mexico
| | - Joaquín Barroso-Flores
- Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM, Unidad San Cayetano 50200 Toluca de lerdo México
- Instituto de Química, Universidad Nacional Autónoma de México Circuito Exterior S/N, Ciudad Universitaria, alcaldía de Coyoacán CP 04510 Ciudad de México México
| | - Masaaki Nakamoto
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima 739-8526 Japan
| | - Yohsuke Yamamoto
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima 739-8526 Japan
| | - Nao Tsunoji
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University 1-4-1 Kagamiyama Higashi-Hiroshima 739-8527 Japan
| | - Rong Shang
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima 739-8526 Japan
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14
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Fontaine FG, Desrosiers V. Boron Lewis Pair Mediated C–H Activation and Borylation. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/a-1561-7953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractIn the few past years, the chemistry of frustrated Lewis pairs (FLP) has enabled a plethora of transformations that would otherwise only be possible using transition metal catalysts. Of particular interest are C–H bond activation and borylation reactions, which are the subject of this review. The FLP borylation chemistry is compared with the early borylation methodologies using strongly electrophilic borenium ions. We present the mechanism of the C–H borylation using inter- and intramolecular Lewis pairs, along with some applications of these transformations.1 Introduction2 Electrophilic Borylation3 Intramolecular or Directed Electrophilic Borylation4 Intermolecular FLP-Mediated C–H Borylation5 Stoichiometric Borylation by Intramolecular FLPs5.1 Csp–H Borylation5.2 Csp2–H Borylation5.3 Csp3–H Borylation6 Catalytic Borylation by Intramolecular FLPs7 Catalytic Borylation by Self-Assembled FLPs8 Conclusion
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15
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Liu X, Li X, Yao X, Zhao W, Liu L. Effects of Ionic Liquids on the Thermodynamics of Hydrogen Activation by Frustrated Lewis Pairs: A Density Functional Theory Study*. Chemphyschem 2021; 22:968-974. [PMID: 33749087 DOI: 10.1002/cphc.202100093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/15/2021] [Indexed: 11/05/2022]
Abstract
Nowadays, hydrogen activation by frustrated Lewis pairs (FLPs) and their applications are one of the emerging research topics in the field of catalysis. Previous studies have shown that the thermodynamics of this reaction is determined by electronic structures of FLPs and solvents. Herein, we investigated systems consisting of typical FLPs and ionic liquids (ILs), which are well known by their large number of types and excellent solvent effects. The density functional theory (DFT) calculations were performed to study the thermodynamics for H2 activation by both inter- and intra-molecular FLPs, as well as the individual components. The results show that the computed overall Gibbs free energies in ILs are more negative than that computed in toluene. Through the thermodynamics partitioning, we find that ILs favor the H-H cleavage elemental step over the elemental steps of proton attachment, hydride attachment and zwitterionic stabilization. Moreover, the results show that these effects are strongly dependent on the type of FLPs, where intra-molecular FLPs are more affected compared to the inter-molecular FLPs.
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Affiliation(s)
- Xiaoqing Liu
- School of Environment and Safety Engineering, North University of China, Taiyuan, 030051, China
| | - Xue Li
- School of Environment and Safety Engineering, North University of China, Taiyuan, 030051, China
| | - Xiaoqian Yao
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100049, China
| | - Weizhen Zhao
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100049, China
| | - Lei Liu
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100049, China
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16
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Dhiman A, Giribabu L, Trivedi R. π-Conjugated Materials Derived From Boron-Chalcogenophene Combination. A Brief Description of Synthetic Routes and Optoelectronic Applications. CHEM REC 2021; 21:1738-1770. [PMID: 33844422 DOI: 10.1002/tcr.202100039] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/19/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022]
Abstract
Functional materials composed of Boron-chalcogenophene conjugates have emerged as promising ensemble featuring commendable optoelectronic properties. This review describes the categories, synthetic routes and optoelectronic applications of a range of boron-chalcogenophene conjugates. Conjugation and linking of different types of tri- and tetra-coordinated boron moieties with chalcogenophenes have remained an important strategy for constructing a range of functional materials. Synthetic protocols have been devised to efficiently prepare such chemically robust conjugates, often exhibiting a myriad of photophysical properties, redox capabilities and also solid-state behaviors. Tin-boron and silicon-boron exchange protocols have been efficiently adapted to access these boron-chalcogenophenes. Few other commonly used methods namely, hydroboration of alkynes as well as electrophilic borylations are also mentioned. The chemical and electronic properties of such boron-chalcogenophene conjugates are directly influenced by the strong Lewis acid character of trivalent boranes which can further alter the intra- and inter- molecular Lewis acid-base interactions. Apart from the synthetic protocols, recent advances in the application of these boron-chalcogenophene conjugates towards analyte sensing, organic electronics, molecular switches and several other aspects will be discussed in this review.
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Affiliation(s)
- Ankita Dhiman
- Catalysis and Fine Chemicals Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, Uppal Road, Tarnaka, Hyderabad,, 500007, Telangana, India
| | - Lingamallu Giribabu
- Polymers and Functional Materials Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, Uppal Road, Tarnaka, Hyderabad, 500007, Telangana, India.,Professor (AcSIR), Academy of Scientific and Innovative Research, AcSIR Headquarters, CSIR-HRDC campus Sector 19, Kamala Nehru Nagar, Ghaziabad, U.P., 201 002, India
| | - Rajiv Trivedi
- Catalysis and Fine Chemicals Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, Uppal Road, Tarnaka, Hyderabad,, 500007, Telangana, India.,Professor (AcSIR), Academy of Scientific and Innovative Research, AcSIR Headquarters, CSIR-HRDC campus Sector 19, Kamala Nehru Nagar, Ghaziabad, U.P., 201 002, India
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17
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Ayyappan R, Coppel Y, Vendier L, Ghosh S, Sabo-Etienne S, Bontemps S. Synthesis and reactivity of phosphine borohydride compounds. Chem Commun (Camb) 2021; 57:375-378. [PMID: 33325466 DOI: 10.1039/d0cc07072f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Four lithium phosphine borohydride compounds featuring phenyl and naphthyl linkers have been synthesized. In-depth NMR analysis affords evidence for non-bonded through space P-B coupling. Reactivity towards CO2 leads to LiH transfer and to the quantitative formation of the corresponding ambiphilic phosphine-borane products.
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Affiliation(s)
- Ramaraj Ayyappan
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 04, France.
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18
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Greb L, Ebner F, Ginzburg Y, Sigmund LM. Element‐Ligand Cooperativity with p‐Block Elements. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000449] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Lutz Greb
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 275 69120 Heidelberg Germany
| | - Fabian Ebner
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 275 69120 Heidelberg Germany
| | - Yael Ginzburg
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 275 69120 Heidelberg Germany
| | - Lukas M. Sigmund
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 275 69120 Heidelberg Germany
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19
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Kim J, Lee T, Ryu JY, Lee YH, Lee J, Jung J, Lee MH. Highly Emissive ortho-Donor–Acceptor Triarylboranes: Impact of Boryl Acceptors on Luminescence Properties. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00185] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Juhee Kim
- Department of Chemistry, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Taehwan Lee
- Department of Chemistry, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Ji Yeon Ryu
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Young Hoon Lee
- Department of Chemistry, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Junseong Lee
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jaehoon Jung
- Department of Chemistry, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Min Hyung Lee
- Department of Chemistry, University of Ulsan, Ulsan 44610, Republic of Korea
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20
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El‐Hamdi M, Timoshkin AY. Hydrogen splitting by pyramidalized 13–15 donor–acceptor cryptands: A computational study. J Comput Chem 2019; 40:1892-1901. [DOI: 10.1002/jcc.25845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 04/05/2019] [Accepted: 04/08/2019] [Indexed: 11/12/2022]
Affiliation(s)
- Majid El‐Hamdi
- Institute of ChemistrySt. Petersburg State University Universitetskaya nab. 7/9, St. Petersburg 199034 Russian Federation
| | - Alexey Y. Timoshkin
- Institute of ChemistrySt. Petersburg State University Universitetskaya nab. 7/9, St. Petersburg 199034 Russian Federation
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21
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Vasko P, Fuentes MÁ, Hicks J, Aldridge S. Reversible O–H bond activation by an intramolecular frustrated Lewis pair. Dalton Trans 2019; 48:2896-2899. [DOI: 10.1039/c9dt00228f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The interactions of the O–H bonds in alcohols, water and phenol with dimethylxanthene-derived frustrated Lewis pairs (FLPs) have been probed.
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Affiliation(s)
- Petra Vasko
- Department of Chemistry
- University of Oxford
- Inorganic Chemistry Laboratory
- Oxford
- UK
| | - M. Ángeles Fuentes
- Department of Chemistry
- University of Oxford
- Inorganic Chemistry Laboratory
- Oxford
- UK
| | - Jamie Hicks
- Department of Chemistry
- University of Oxford
- Inorganic Chemistry Laboratory
- Oxford
- UK
| | - Simon Aldridge
- Department of Chemistry
- University of Oxford
- Inorganic Chemistry Laboratory
- Oxford
- UK
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22
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Schürmann CJ, Herbst-Irmer R, Teuteberg TL, Kratzert D, Erker G, Mata RA, Stalke D. Experimental charge density study on FLPs and a FLP reaction product. Z KRIST-CRYST MATER 2018. [DOI: 10.1515/zkri-2018-2061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The charge density distribution of the intramolecular frustrated Lewis pair (FLP) Mes2PCH2CH2B(C6F5)2 (1), the phosphinimine HNPMes2CH2CH2B(C6F5)2 (2), as well as a FLP homologue with nitrogen NEt2CHPhCH2B(C6F5)2 (3) were investigated with Bader’s quantum theory of atoms in molecules (QTAIM). The charge densities were derived from both experimental high-resolution X-ray diffraction data (2, 3) and theoretical calculations (1, 3). The QTAIM analysis for the FLPs 1 and 3 showed the prominent B-pnictogen interaction to be weak dative bonds without significant charge-transfer. This holds also true for the B–N–bond of 2. The nitrogen atom is negatively charged, due to a charge transfer from phosphorous and shows features of a sp2-hybridization. The bond is therefore best described as a non-hypervalent Pδ+–Nδ− moiety.
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Affiliation(s)
| | - Regine Herbst-Irmer
- Institut für Anorganische Chemie, Universität Göttingen , Tammannstraße 4 , Göttingen 37077 , Germany
| | | | - Daniel Kratzert
- Institut für Anorganische Chemie, Universität Göttingen , Tammannstraße 4 , Göttingen 37077 , Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Universität Münster , Corrensstraße 40 , Münster 48149 , Germany
| | - Ricardo A. Mata
- Institut für Physikalische Chemie, Universität Göttingen , Tammannstraße 6 , Göttingen 37077 , Germany
| | - Dietmar Stalke
- Institut für Anorganische Chemie, Universität Göttingen , Tammannstraße 4 , Göttingen 37077 , Germany
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23
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Spittler M, Helmecke L, Czekelius C. Mechanistic Insights into FLP-Catalyzed Iodoperfluoroalkylations. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800866] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Michael Spittler
- Institute for Organic Chemistry and Macromolecular Chemistry; Heinrich-Heine-Universität Düsseldorf; Universitätsstr. 1 40225 Düsseldorf Germany
| | - Lucas Helmecke
- Institute for Organic Chemistry and Macromolecular Chemistry; Heinrich-Heine-Universität Düsseldorf; Universitätsstr. 1 40225 Düsseldorf Germany
| | - Constantin Czekelius
- Institute for Organic Chemistry and Macromolecular Chemistry; Heinrich-Heine-Universität Düsseldorf; Universitätsstr. 1 40225 Düsseldorf Germany
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24
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Rational design of FLP catalysts for reversible H2 activation: A DFT study of the geometric and electronic effects. CHINESE CHEM LETT 2018. [DOI: 10.1016/j.cclet.2018.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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25
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Wu D, Liu A, Jia D. Density functional reactivity theory characterizing the reactivity of frustrated Lewis pairs. COMPUT THEOR CHEM 2018. [DOI: 10.1016/j.comptc.2018.03.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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26
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Wang T, Daniliuc CG, Mück-Lichtenfeld C, Kehr G, Erker G. Formation of Reactive π-Conjugated Frustrated N/B Pairs by Borane-Induced Propargyl Amine Rearrangement. J Am Chem Soc 2018; 140:3635-3643. [PMID: 29444567 DOI: 10.1021/jacs.7b11958] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
N-Propargyltetramethylpiperidine reacts with a series of trans-alkenyl-B(C6F5)2 compounds to give the substituted alkenyl-bridged frustrated N/B Lewis pairs 5. Their structures and spectroscopic features indicate a pronounced participation of the mesomeric s-trans-iminium/borata-alkene resonance form. The compounds are thought to be formed in a stepwise addition/rearrangement process which is initiated by a trans-1,2-amine/borane FLP addition to the carbon-carbon triple bond to generate a reactive zwitterionic aziridinium/alkenylborate intermediate. Subsequent alkenylborate attack leads to opening of the activated three-membered heterocycle with clean formation of the products 5a-c. Treatment of the propargyl-TMP substrate with B(C6F5)3 gave a stable example of such an aziridinium/borate betaine, which was isolated and amply characterized. The products 5a-c are active N/B FLPs. They split dihydrogen heterolytically under mild conditions to give the respective NH+/BH- products 9a-c. These contain Z-configurated core C═C double bonds, which indicates rotational equilibration around the central C-C bond of 5a-c during this reaction. Structural and chemical features of the 5c system were analyzed by DFT calculations.
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Affiliation(s)
- Tongdao Wang
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Christian Mück-Lichtenfeld
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
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27
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Wang T, Kehr G, Daniliuc CG, Erker G. Metal-Free Carbonylation Route to a Reactive Borataepoxide System. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tongdao Wang
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
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28
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Tirfoin R, Gilbert J, Kelly MJ, Aldridge S. Frustrated Lewis pairs incorporating the bifunctional Lewis acid 1,1'-fc{B(C 6F 5) 2} 2: reactivity towards small molecules. Dalton Trans 2018; 47:1588-1598. [PMID: 29323374 DOI: 10.1039/c7dt04136e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Applications of the bifunctional ferrocenediyl Lewis acid 1,1'-fc{B(C6F5)2}2 in frustrated Lewis pair (FLP) chemistry are described. The coordination (or otherwise) of a range of sterically encumbered C-, N- and P-centred Lewis bases has been investigated, with lutidine, tetramethylpiperidine, PPh3, PtBu3 and the expanded ring carbene 6Dipp being found to be sterically incapable of coordinate bond formation. The chemistry of a range of these FLPs in the presence of H2O, NH3, CO2 and cyclohexylisocyanate (CyNCO) has been investigated, with the patterns of reactivity identified including simple coordination chemistry, E-H bond cleavage and C-B insertion.
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Affiliation(s)
- Rémi Tirfoin
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, UKOX1 3QR.
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29
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Ilic S, Alherz A, Musgrave CB, Glusac KD. Thermodynamic and kinetic hydricities of metal-free hydrides. Chem Soc Rev 2018; 47:2809-2836. [DOI: 10.1039/c7cs00171a] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Thermodynamic and kinetic hydricities provide useful guidelines for the design of hydride donors with desirable properties for catalytic chemical reductions.
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Affiliation(s)
- Stefan Ilic
- Department of Chemistry
- University of Illinois at Chicago
- Chicago
- USA
- Chemical Sciences and Engineering Division
| | - Abdulaziz Alherz
- Department of Chemical and Biological Engineering
- University of Colorado
- Boulder
- USA
| | - Charles B. Musgrave
- Department of Chemical and Biological Engineering
- University of Colorado
- Boulder
- USA
- Department of Chemistry and Biochemistry
| | - Ksenija D. Glusac
- Department of Chemistry
- University of Illinois at Chicago
- Chicago
- USA
- Chemical Sciences and Engineering Division
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30
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Fontaine FG, Courtemanche MA, Légaré MA, Rochette É. Design principles in frustrated Lewis pair catalysis for the functionalization of carbon dioxide and heterocycles. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.05.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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31
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Rochette É, Courtemanche MA, Fontaine FG. Frustrated Lewis Pair Mediated Csp3−H Activation. Chemistry 2017; 23:3567-3571. [DOI: 10.1002/chem.201700390] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Indexed: 01/12/2023]
Affiliation(s)
- Étienne Rochette
- Département de Chimie, Centre de Catalyse et Chimie Verte (C3V); Université Laval; 1045 Avenue de la Médecine Québec G1V 0A6 Québec Canada
| | - Marc-André Courtemanche
- Département de Chimie, Centre de Catalyse et Chimie Verte (C3V); Université Laval; 1045 Avenue de la Médecine Québec G1V 0A6 Québec Canada
| | - Frédéric-Georges Fontaine
- Département de Chimie, Centre de Catalyse et Chimie Verte (C3V); Université Laval; 1045 Avenue de la Médecine Québec G1V 0A6 Québec Canada
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32
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Son JH, Tamang SR, Fostvedt JI, Hoefelmeyer JD. Dehydrodechlorination of Methylene Chloride, Chloroform, and Chlorodiphenylmethane in the Presence of Ga/N Lewis Pairs. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jung-Ho Son
- Department of Chemistry, University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - Sem Raj Tamang
- Department of Chemistry, University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - Jade I. Fostvedt
- Department of Chemistry, University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
| | - James D. Hoefelmeyer
- Department of Chemistry, University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, United States
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Elmer LM, Kehr G, Daniliuc CG, Siedow M, Eckert H, Tesch M, Studer A, Williams K, Warren TH, Erker G. The Chemistry of a Non-Interacting Vicinal Frustrated Phosphane/Borane Lewis Pair. Chemistry 2016; 23:6056-6068. [PMID: 27925311 DOI: 10.1002/chem.201603954] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 09/23/2016] [Indexed: 12/14/2022]
Abstract
The dimesitylphosphinocyclopentene/HB(C6 F5 )2 -derived vicinal trans-1,2-P/B frustrated Lewis pair (FLP) 4 shows no direct phosphane-borane interaction. Toward some reagents it behaves similar to an intermolecular FLP; it cleaves dihydrogen, deprotonates terminal alkynes, and adds to organic carbonyl compounds including CO2 . It shows typical intramolecular FLP reaction modes (cooperative 1,1-additions) to mesityl azide, to carbon monoxide, and to NO. The latter reaction yields a persistent P/B FLPNO nitroxide radical, which undergoes H-atom abstraction reactions. The FLP 4 serves as a template for the CO reduction by [HB(C6 F5 )2 ] to generate a FLP-η2 -formylborane. The formylborane moiety is removed from the FLP template by reaction with pyridine to yield a genuine pyridine stabilized formylborane that undergoes characteristic borane carbaldehyde reactions (Wittig olefination, imine formation). Most new products were characterized by X-ray diffraction.
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Affiliation(s)
- Lisa-Maria Elmer
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Melanie Siedow
- Institut für Physikalische Chemie, Universutät Münster, Corrensstraße 28/30, 48149, Münster, Germany
| | - Hellmut Eckert
- Institut für Physikalische Chemie, Universutät Münster, Corrensstraße 28/30, 48149, Münster, Germany.,Instituto de Física Sao Carlos, Universidade de Sao Paulo, CP 369, 13560-970, Sao Carlos, SP, Brasil
| | - Matthias Tesch
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Kamille Williams
- Georgetown University, Department of Chemistry, Box 571227, Washington DC, 20057-1227, USA
| | - Timothy H Warren
- Georgetown University, Department of Chemistry, Box 571227, Washington DC, 20057-1227, USA
| | - Gerhard Erker
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149, Münster, Germany
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34
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Yepes D, Jaque P, Fernández I. Deeper Insight into the Factors Controlling H2Activation by Geminal Aminoborane-Based Frustrated Lewis Pairs. Chemistry 2016; 22:18801-18809. [DOI: 10.1002/chem.201603889] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Diana Yepes
- Departamento de Ciencias Químicas; Facultad de Ciencias Exactas; Universidad Andres Bello; Av. República 275 Santiago Chile
- Nucleus Millennium Chemical Processes and Catalysis (CPC); Vicuña Mackenna 4860, Casilla 306, Correo 22 Santiago Chile
| | - Pablo Jaque
- Departamento de Ciencias Químicas; Facultad de Ciencias Exactas; Universidad Andres Bello; Av. República 275 Santiago Chile
- Nucleus Millennium Chemical Processes and Catalysis (CPC); Vicuña Mackenna 4860, Casilla 306, Correo 22 Santiago Chile
| | - Israel Fernández
- Departamento de Química Orgánica I; Facultad de Ciencias Químicas; Universidad Complutense de Madrid; 28040 Madrid Spain
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35
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Özgün T, Chen GQ, Daniliuc CG, McQuilken AC, Warren TH, Knitsch R, Eckert H, Kehr G, Erker G. Unsaturated Vicinal Frustrated Lewis Pair Formation by Electrocyclic Ring Closure and Their Reaction with Nitric Oxide. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00627] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Thomas Özgün
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Guo-Qiang Chen
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Alison C. McQuilken
- Department
of Chemistry, Georgetown University, Box 571227, Washington, D.C. 20057-1227, United States
| | - Timothy H. Warren
- Department
of Chemistry, Georgetown University, Box 571227, Washington, D.C. 20057-1227, United States
| | - Robert Knitsch
- Institut
für Physikalische Chemie, Westfälische Wilhelms-Universität, Corrensstrasse 30, 48149 Münster, Germany
| | - Hellmut Eckert
- Institut
für Physikalische Chemie, Westfälische Wilhelms-Universität, Corrensstrasse 30, 48149 Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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36
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Chen GQ, Kehr G, Daniliuc CG, Mück-Lichtenfeld C, Erker G. Formation of Thermally Robust Frustrated Lewis Pairs by Electrocyclic Ring Closure Reactions. Angew Chem Int Ed Engl 2016; 55:5526-30. [PMID: 27010753 DOI: 10.1002/anie.201510994] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/22/2016] [Indexed: 11/08/2022]
Abstract
The phosphorus/boron-substituted hexatriene systems 6 undergo thermally induced electrocyclic ring closure to yield the cyclohexadiene-derived P/B frustrated Lewis pairs (FLPs) 7. Subsequent TEMPO oxidation gives the phenylene-bridged FLPs 8. Both systems activate dihydrogen and the thermally robust FLPs undergo carbon-carbon coupling reactions at a mesityl group upon treatment with dimethyl acetylenedicarboxylate at elevated temperatures.
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Affiliation(s)
- Guo-Qiang Chen
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | | | - Gerhard Erker
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149, Münster, Germany.
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37
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Chen G, Kehr G, Daniliuc CG, Mück‐Lichtenfeld C, Erker G. Formation of Thermally Robust Frustrated Lewis Pairs by Electrocyclic Ring Closure Reactions. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201510994] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Guo‐Qiang Chen
- Organisch-Chemisches Institut der Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut der Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut der Universität Münster Corrensstraße 40 48149 Münster Germany
| | | | - Gerhard Erker
- Organisch-Chemisches Institut der Universität Münster Corrensstraße 40 48149 Münster Germany
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38
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Courtemanche MA, Rochette É, Légaré MA, Bi W, Fontaine FG. Reversible hydrogen activation by a bulky haloborane based FLP system. Dalton Trans 2016; 45:6129-35. [DOI: 10.1039/c5dt03916a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The FLP species bis(2-(TMP)phenyl)chloroborane was prepared as a monomeric Frustrated Lewis Pair displaying no B–N interaction. Species 1 reacts with H2 to generate reversibly the zwitterionic H2 activation product.
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Affiliation(s)
| | | | | | - Wenhua Bi
- Département de Chimie
- Université Laval
- Québec
- Canada
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39
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Frömel S, Daniliuc CG, Bannwarth C, Grimme S, Bussmann K, Kehr G, Erker G. Indirect synthesis of a pair of formal methane activation products at a phosphane/borane frustrated Lewis pair. Dalton Trans 2016; 45:19230-19233. [DOI: 10.1039/c6dt04206f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The endergonic formal FLP methane activation products were obtained by an indirect stepwise synthesis and shown to be kinetically stable.
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Affiliation(s)
- Silke Frömel
- Organisch-Chemisches Institut
- Universität Münster
- 48149 Münster
- Germany
| | | | - Christoph Bannwarth
- Mulliken Center for Theoretical Chemistry
- Institut für Physikalische und Theoretische Chemie
- Universität Bonn
- D-53115 Bonn
- Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry
- Institut für Physikalische und Theoretische Chemie
- Universität Bonn
- D-53115 Bonn
- Germany
| | - Kathrin Bussmann
- Organisch-Chemisches Institut
- Universität Münster
- 48149 Münster
- Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut
- Universität Münster
- 48149 Münster
- Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut
- Universität Münster
- 48149 Münster
- Germany
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40
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Chen GQ, Türkyilmaz F, Daniliuc CG, Bannwarth C, Grimme S, Kehr G, Erker G. Enamine/butadienylborane cycloaddition in the frustrated Lewis pair regime. Org Biomol Chem 2015; 13:10477-86. [PMID: 26330093 DOI: 10.1039/c5ob01602a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The dienylborane 2a was prepared by regioselective alkyne hydroboration of the conjugated enyne 1a with Piers' borane [HB(C6F5)2]. Its reaction with a series of acetophenone derived enamines 3 resulted in the formation of the strong enamine β-carbon adduct with the borane Lewis acid (4). In contrast B-C adduct formation between the dienylborane 2a and a series of much more bulky cyclohexanone derived enamines (6) is rapidly reversible above ca.-30 °C and then leads to the formation of the [4 + 2]cycloaddition products 8. A DFT study revealed that this reaction is probably taking a stepwise route, proceeding by means of enamine addition to the dienylborane terminus to generate a zwitterionic borata-alkene/iminium ion intermediate that undergoes rapid subsequent ring closure. Heating of the products 8 led to amidoborane elimination from the vicinal amino/borane pair at the product framework to give the respective hexahydronaphthalene product 10. Subsequent treatment with TEMPO (2 equiv.) resulted in selective oxidation of the unsaturated ring to give the respective tetrahydronaphthalene derivative 12.
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Affiliation(s)
- Guo-Qiang Chen
- Organisch-Chemisches Institut, Universität Münster, Corrensstraβe 40, 48149 Münster, Germany.
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41
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Chloro({2-[mesityl(quinolin-8-yl-κN)boryl]-3,5-dimethyl-phenyl}methyl-κC)palladium(II) as a catalyst for Heck reactions. Molecules 2015; 20:12979-91. [PMID: 26193250 PMCID: PMC6332355 DOI: 10.3390/molecules200712979] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 07/09/2015] [Accepted: 07/15/2015] [Indexed: 11/17/2022] Open
Abstract
We recently reported an air and moisture stable 16-electron borapalladacycle formed upon combination of 8-quinolyldimesitylborane with bis(benzonitrile)dichloropalladium(II). The complex features a tucked mesityl group formed upon metalation of an ortho-methyl group on a mesityl; however it is unusually stable due to contribution of the boron pz orbital in delocalizing the carbanion that gives rise to an η4-boratabutadiene fragment coordinated to Pd(II), as evidenced from crystallographic data. This complex was observed to be a highly active catalyst for the Heck reaction. Data of the catalyst activity are presented alongside data found in the literature, and initial comparison reveals that the borapalladacycle is quite active. The observed catalysis suggests the borapalladacycle readily undergoes reductive elimination; however the Pd(0) complex has not yet been isolated. Nevertheless, the ambiphilic ligand 8-quinolyldimesitylborane may be able to support palladium in different redox states.
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42
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Rochette É, Courtemanche MA, Pulis AP, Bi W, Fontaine FG. Ambiphilic Frustrated Lewis Pair Exhibiting High Robustness and Reversible Water Activation: Towards the Metal-Free Hydrogenation of Carbon Dioxide. Molecules 2015; 20:11902-14. [PMID: 26132911 PMCID: PMC6331835 DOI: 10.3390/molecules200711902] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/04/2015] [Accepted: 06/19/2015] [Indexed: 12/15/2022] Open
Abstract
The synthesis and structural characterization of a phenylene-bridged Frustrated Lewis Pair (FLP) having a 2,2,6,6‑tetramethylpiperidine (TMP) as the Lewis base and a 9-borabicyclo[3.3.1]nonane (BBN) as the Lewis acid is reported. This FLP exhibits unique robustness towards the products of carbon dioxide hydrogenation. The compound shows reversible splitting of water, formic acid and methanol while no reaction is observed in the presence of excess formaldehyde. The molecule is incredibly robust, showing little sign of degradation after heating at 80 °C in benzene with 10 equiv. of formic acid for 24 h. The robustness of the system could be exploited in the design of metal-free catalysts for the hydrogenation of carbon dioxide.
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Affiliation(s)
- Étienne Rochette
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Marc-André Courtemanche
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Alexander P Pulis
- Department of Chemistry, University of Toronto, 80 George Street, Toronto, ON M5S 3H6, Canada.
| | - Wenhua Bi
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Frédéric-Georges Fontaine
- Department of Chemistry, Centre de Catalyse et Chimie Verte (C3V), Université Laval, 1045 Avenue de la Médecine, Québec, QC G1V 0A6, Canada.
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43
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Stephan DW, Erker G. Chemie frustrierter Lewis-Paare: Entwicklung und Perspektiven. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201409800] [Citation(s) in RCA: 481] [Impact Index Per Article: 53.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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Stephan DW, Erker G. Frustrated Lewis pair chemistry: development and perspectives. Angew Chem Int Ed Engl 2015; 54:6400-41. [PMID: 25974714 DOI: 10.1002/anie.201409800] [Citation(s) in RCA: 1327] [Impact Index Per Article: 147.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Indexed: 12/17/2022]
Abstract
Frustrated Lewis pairs (FLPs) are combinations of Lewis acids and Lewis bases in solution that are deterred from strong adduct formation by steric and/or electronic factors. This opens pathways to novel cooperative reactions with added substrates. Small-molecule binding and activation by FLPs has led to the discovery of a variety of new reactions through unprecedented pathways. Hydrogen activation and subsequent manipulation in metal-free catalytic hydrogenations is a frequently observed feature of many FLPs. The current state of this young but rapidly expanding field is outlined in this Review and the future directions for its broadening sphere of impact are considered.
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Affiliation(s)
- Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George St, Toronto, Ontario M5S3H6 (Canada).
| | - Gerhard Erker
- Organisch Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstr. 40, 48149 Münster (Germany).
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45
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46
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Körte LA, Warner R, Vishnevskiy YV, Neumann B, Stammler HG, Mitzel NW. Intramolecular pyridine-based frustrated Lewis-pairs. Dalton Trans 2015; 44:9992-10002. [DOI: 10.1039/c5dt01068c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Besides a series of pyridine-based Lewis pairs with B(C6F5)2 groups with varying electronic and steric situations and strong intramolecular B–N bonds, 2-[(CH2)4B(C6F5)2]-6-tBu-pyridine was found to behave as a frustrated Lewis pair.
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Affiliation(s)
- Leif A. Körte
- Bielefeld University
- Faculty of Chemistry
- Chair of Inorganic and Structural Chemistry
- Centre for Molecular Materials CM2
- 33615 Bielefeld
| | - Robin Warner
- Bielefeld University
- Faculty of Chemistry
- Chair of Inorganic and Structural Chemistry
- Centre for Molecular Materials CM2
- 33615 Bielefeld
| | - Yury V. Vishnevskiy
- Bielefeld University
- Faculty of Chemistry
- Chair of Inorganic and Structural Chemistry
- Centre for Molecular Materials CM2
- 33615 Bielefeld
| | - Beate Neumann
- Bielefeld University
- Faculty of Chemistry
- Chair of Inorganic and Structural Chemistry
- Centre for Molecular Materials CM2
- 33615 Bielefeld
| | - Hans-Georg Stammler
- Bielefeld University
- Faculty of Chemistry
- Chair of Inorganic and Structural Chemistry
- Centre for Molecular Materials CM2
- 33615 Bielefeld
| | - Norbert W. Mitzel
- Bielefeld University
- Faculty of Chemistry
- Chair of Inorganic and Structural Chemistry
- Centre for Molecular Materials CM2
- 33615 Bielefeld
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47
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Rocchigiani L. Experimental Insights into the Structure and Reactivity of Frustrated Lewis Pairs. Isr J Chem 2014. [DOI: 10.1002/ijch.201400139] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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48
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Hydrogen Activation by Frustrated Lewis Pairs: Insights from Computational Studies. Top Curr Chem (Cham) 2013; 332:157-211. [DOI: 10.1007/128_2012_399] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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49
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Chuong R, Luck KA, Luck RL, Nguyen LP, Phan D, Pignotti LR, Urnezius E, Valente EJ. Ditopic ligands featuring [P,S], [P,P] or [P,B] chelating pockets housed on a protected o-hydroquinone core. J Organomet Chem 2013. [DOI: 10.1016/j.jorganchem.2012.10.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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50
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Klahn M, Spannenberg A, Rosenthal U. Tri-tert-butyl-phospho-nium hy-droxy-tris-(penta-fluoro-phen-yl)borate. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o1549. [PMID: 22590410 PMCID: PMC3344648 DOI: 10.1107/s1600536812018144] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 04/23/2012] [Indexed: 11/17/2022]
Abstract
The ionic title compound, C12H28P+·C18HBF15O−, was obtained by the stoichiometric reaction of tBu3P, B(C6F5)3 and water in toluene. A weak P—H⋯O hydrogen bond is observed in the crystal structure.
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Affiliation(s)
- Marcus Klahn
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
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