1
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Swaby C, Taylor A, Greaney MF. An NHC-Catalyzed Desulfonylative Smiles Rearrangement of Pyrrole and Indole Carboxaldehydes. J Org Chem 2023; 88:12821-12825. [PMID: 37589318 PMCID: PMC10476196 DOI: 10.1021/acs.joc.3c01089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Indexed: 08/18/2023]
Abstract
The use of catalysis methods to enable Smiles rearrangement opens up new substrate classes for arylation under mild conditions. Here, we describe an N-heterocyclic carbene (NHC) catalysis system that accesses indole and pyrrole aldehyde substrates in a desulfonylative Smiles process. The reaction proceeds under mild, transition-metal-free conditions and captures acyl anion reactivity for the synthesis of a diverse array of 2-aroyl indoles and pyrroles from readily available sulfonamide starting materials.
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Affiliation(s)
| | | | - Michael F. Greaney
- Dept. of Chemistry, University of Manchester, Oxford Rd, Manchester, M13 9PL, U.K.
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2
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Versatility of thiourea dioxide as redox agent in globins: case study with myoglobin. Inorganica Chim Acta 2023. [DOI: 10.1016/j.ica.2023.121474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
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3
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Logdi R, Bag A, Tiwari AK. Schematic Design of Metal-Free NHC-Mediated Sequestering and Complete Conversion of SO 2 to Thiocarbonyl S-Oxide Derivatives at Room Temperature. J Phys Chem A 2022; 126:221-229. [PMID: 34995460 DOI: 10.1021/acs.jpca.1c07918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The sequestering and complete conversion of SO2 to valuable chemicals in a metal-free pathway is highly demanded. The recent success of SO2 fixation by N-heterocyclic carbenes instigated further studies in this regard. Previous reports were confined within the carbene-SO2 reaction mechanism and the stability of oxathiirane S-oxide derivatives. The complete conversion of captured SO2 to precious chemicals was not studied. The present inquisition has accomplished the scarcity of the earlier studies. It is observed that in the presence of an excess amount of carbene, the registered SO2 is converted to the ketone derivative and thiocarbonyl S-oxide derivative. An electronic level investigation of these reactions is carried out. From the change of the molecular orbitals along the reaction path, it is concluded that the reaction between the oxathiirane S-oxide derivative and carbene follows a frog's hunting mechanism.
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Affiliation(s)
- Ratan Logdi
- Department of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata, 741246 West Bengal, India
| | - Arijit Bag
- Department of Applied Science, Maulana Abul Kalam Azad University of Technology, West Bengal, Kolkata, 741249 West Bengal, India
| | - Ashwani K Tiwari
- Department of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata, 741246 West Bengal, India
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4
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Guschlbauer J, Vollgraff T, Xie X, Fetoh A, Sundermeyer J. Heavy silylchalcogenido lanthanates synthesis Ph 4P[Cp 3La-ESiMe 3] (E = S, Se, and Te) via fluoride-induced demethylation of dimethylcarbonate to Ph 4P[OCO 2Me] key intermediate. Dalton Trans 2021; 50:13103-13111. [PMID: 34581360 DOI: 10.1039/d1dt02000e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report a new high-yield synthesis of so far not accessible tetraphenylphosphonium methylcarbonate Ph4P[OCO2Me] via solvothermal fluoride-induced demethylation and MeF elimination at Me2CO3 (DMC) by Ph4P-F, structurally characterized as λ5-fluorophosphoran by XRD. The synthetic value of Ph4P[OCO2Me] key compound for preparing nearly all kinds of other Ph4P[anion] salts with perfectly crystallizing (not symmetry frustrated) cation is demonstrated by examples beyond ionic liquid research: a complete set of silylchalcogenide salts Ph4P[ESiMe3] (E = S, Se, and Te) including the first example of a structurally characterized non-coordinating, naked [Te-SiMe3]- anion is presented. With this set of soft Lewis bases and metal organic Lewis acids [Cp3La] at hand, a comprehensive series of crystalline 1 : 1 lanthanate complexes Ph4P[Cp3La-ESiMe3] has been prepared. Their structural features and trends such as complexation induced Si-E bond elongation and a pronounced trend in La-E-Si bond angle contraction with E = S < Se < Te are discussed. Heteronuclear 1H, 13C, 29Si, and 139La NMR studies provide a set of 139La NMR shifts for homologs of heavy chalcogen-lanthanum complexes.
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Affiliation(s)
- Jannick Guschlbauer
- Department of Chemistry and Materials Sciences Center, Philipps-Universität Marburg, Hans Meerwein Straße 4, 35043 Marburg, Germany.
| | - Tobias Vollgraff
- Department of Chemistry and Materials Sciences Center, Philipps-Universität Marburg, Hans Meerwein Straße 4, 35043 Marburg, Germany.
| | - Xiulan Xie
- Department of Chemistry and Materials Sciences Center, Philipps-Universität Marburg, Hans Meerwein Straße 4, 35043 Marburg, Germany.
| | - Ahmed Fetoh
- Department of Chemistry and Materials Sciences Center, Philipps-Universität Marburg, Hans Meerwein Straße 4, 35043 Marburg, Germany. .,Department of Chemistry, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Jörg Sundermeyer
- Department of Chemistry and Materials Sciences Center, Philipps-Universität Marburg, Hans Meerwein Straße 4, 35043 Marburg, Germany.
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5
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Logdi R, Bag A, Tiwari AK. Competitive Reactivity of SO 2 and NO 2 with N-Heterocyclic Carbene: A Mechanistic Study. J Phys Chem A 2021; 125:5718-5725. [PMID: 34170129 DOI: 10.1021/acs.jpca.1c02466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent DFT based molecular engineering to obtain stable oxathiirane S-oxide derivatives evokes the recommencement of the use of carbenes for the sequestering of SO2, which has been kept separate so far. Carbene is one of the key chemicals for the sequestering of various premier greenhouse gases like CO2, CO, N2O, etc. In this respect, a comparative study of the reactivity of carbenes with variant greenhouse gases is highly demanding. The present investigation is engrossed in the comparative reactivity of SO2 and NO2 with carbenes. All three selected carbenes are highly susceptible to SO2 and NO2. Through an immaculate mechanistic study, we are able to corroborate that the end product of the carbene-SO2 reaction is an adduct which has a preferable structure having a six-membered ring with hydrogen bonding instead of ketone and SO with higher thermodynamic stability than the corresponding oxathiirane S-oxide derivative. Carbene reacts with NO2 to form a stable carbene N, N-dioxide derivative which forms vibrationally excited oxaziridine N-oxide which rapidly dissociates to form a ketone derivative. The formation of carbene S, S-dioxide and carbene N, N-dioxide is a barrierless process. The dissociation of oxaziridene N-oxide is also a barrierless process.
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Affiliation(s)
- Ratan Logdi
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, 741246 West-Bengal, India
| | - Arijit Bag
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, 741246 West-Bengal, India
| | - Ashwani K Tiwari
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, 741246 West-Bengal, India
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6
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Vollgraff T, Sundermeyer J. Highly Selective Ortho-Directed Dicarboxylation of Cyclopentadiene by Methylcarbonates and CO 2 or COS - First Insight into Co-ordination Chemistry of New Ambident Ligands. Chemistry 2021; 27:8517-8527. [PMID: 33851453 PMCID: PMC8252773 DOI: 10.1002/chem.202100300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Indexed: 11/25/2022]
Abstract
This research presents the highly regioselective syntheses of 1,2-dicarboxylated cyclopentadienide salts [Cat]2 [C5 H3 (CO2 )2 H] by reaction of a variety of organic cation methylcarbonate salts [Cat]OCO2 Me (Cat=NR4 + , PR4 + , Im+ ) with cyclopentadiene (CpH) or by simply reacting organic cation cyclopentadienides Cat[Cp] (Cat=NR4 + , PR4 + , Im+ ) with CO2 . One characteristic feature of these dianionic ligands is the acidic proton delocalized in an intramolecular hydrogen bridge (IHB) between the two carboxyl groups, as studied by 1 H NMR spectroscopy and XRD analyses. The reaction cannot be stopped after the first carboxylation. Therefore, we propose a Kolbe-Schmitt phenol-carboxylation related mechanism where the acidic proton of the monocarboxylic acid intermediate plays an ortho-directing and CO2 activating role for the second kinetically accelerated CO2 addition step exclusively in ortho position. The same and related thiocarboxylates [Cat]2 [C5 H3 (COS)2 H] are obtained by reaction of COS with Cat[Cp] (Cat=NR4 + , PR4 + , Im+ ). A preliminary study on [Cat]2 [C5 H3 (CO2 )2 H] reveals, that its soft and hard coordination sites can selectively be addressed by soft Lewis acids (Mo0 , Ru2+ ) and hard Lewis acids (Al3+ , La3+ ).
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Affiliation(s)
- Tobias Vollgraff
- Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften (WZMW)Philipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - Jörg Sundermeyer
- Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften (WZMW)Philipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
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7
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Li Z, Ji P, Cheng JP. Brönsted Basicities and Nucleophilicities of N-Heterocyclic Olefins in Solution: N-Heterocyclic Carbene versus N-Heterocyclic Olefin. Which Is More Basic, and Which Is More Nucleophilic? J Org Chem 2021; 86:2974-2985. [PMID: 33464082 DOI: 10.1021/acs.joc.0c02838] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A Brönsted basicity scale comprising nine representative N-heterocyclic olefins (NHOs) was established by measuring the equilibrium acidities of their corresponding precursors in DMSO using an ultraviolet-visible spectroscopic method. The basicities (pKaHs) of the investigated NHOs cover a range from 14.7 to 24.1. The basicities of unsaturated NHOs are stronger than those of their N-heterocyclic carbene (NHC) analogues; however, the basicities for the saturated ones are much weaker than those of their NHC analogues, which is largely due to the aromatization effect that intrinsically influences the acidic dissociations of NHC and NHO precursors. The nucleophilicities of four NHOs were measured photometrically by monitoring the kinetics of reactions of these NHOs with common reference electrophiles for quantifying nucleophilic reactivities. In general, the nucleophilicity of the NHOs is much stronger than that of commonly used Lewis bases such as Ph3P or DMAP [4-(dimethylamino)pyridine] but weaker than that of their NHC analogues; however, caution should be taken when generalizing this conclusion to a wide range of electrophiles with distinctively electronic and structural properties.
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Affiliation(s)
- Zhen Li
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Pengju Ji
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Jin-Pei Cheng
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China.,State Key Laboratory of Elemento-organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
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8
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Guschlbauer J, Sundermeyer J. Heavy Chalcogenide-Based Ionic Liquids in Syntheses of Metal Chalcogenide Materials near Room Temperature. ChemistryOpen 2021; 10:92-96. [PMID: 33565731 PMCID: PMC7874248 DOI: 10.1002/open.202000346] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/18/2020] [Indexed: 12/02/2022] Open
Abstract
This minireview describes two strategically different and unexplored approaches to use ionic liquids (IL) containing weakly solvated and highly reactive chalcogenide anions [E-SiMe3 ]- and [E-H]- of the heavy chalcogens (E=S, Se, Te) in materials synthesis near room temperature. The first strategy involves the synthesis of unprecedented trimethylsilyl chalcogenido metalates Cat+ [M(E-SiMe3 )n ]- (Cat=organic IL cation) of main group and transition metals (M=Ga, In, Sn, Zn, Cu, Ag, Au). These fully characterized homoleptic metalates serve as thermally metastable precursors in low-temperature syntheses of binary, ternary and even quaternary chalcogenide materials such as CIGS and CZTS relevant for semiconductor and photovoltaics (PV) applications. Furthermore, thermally and protolytically metastable coinage metalates Cat+ [M(ESiMe3 )2 ]- (M=Cu, Ag, Au; E=S, Se) are accessible. Finally, the use of precursors BMPyr[E-SiMe3 ] (E=Se,Te; BMPyr=1-butyl-1-methylpyrrolidinium) as sources of activated selenium and tellurium in the synthesis of high-grade thermoelectric nanoparticles Bi2 Se3 and Bi2 Te3 is shortly highlighted. The second synthesis strategy involves the metalation of ionic liquids Cat[S-H] and Cat[Se-H] by protolytically highly active metal alkyls or amides Rn M. This rather general approach towards unknown chalcogenido metalates Catm [Rn-1 M(E)]m (E=S, Se) will be demonstrated in a research paper following this short review head-to-tail.
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Affiliation(s)
- Jannick Guschlbauer
- Fachbereich Chemie and Materials Science CenterPhilipps-UniversitätHans-Meerwein-Str. 435032MarburgGermany
| | - Jörg Sundermeyer
- Fachbereich Chemie and Materials Science CenterPhilipps-UniversitätHans-Meerwein-Str. 435032MarburgGermany
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9
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Tintori G, Fall A, Assani N, Zhao Y, Bergé-Lefranc D, Redon S, Vanelle P, Broggi J. Generation of powerful organic electron donors by water-assisted decarboxylation of benzimidazolium carboxylates. Org Chem Front 2021. [DOI: 10.1039/d0qo01488e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
In situ and easy generation of organic electron donors from water-activation of carboxylate precursors allows OED-promoted intermolecular radical addition reactions.
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Affiliation(s)
- Guillaume Tintori
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
| | - Arona Fall
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
| | - Nadhrata Assani
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
| | - Yuxi Zhao
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
| | | | - Sébastien Redon
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
| | - Patrice Vanelle
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
| | - Julie Broggi
- Aix Marseille Univ
- CNRS
- Institut de Chimie Radicalaire ICR
- Faculté de Pharmacie
- 13005 Marseille
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10
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Wang Z, Niu QH, Xue XS, Ji P. The Brönsted Basicities of N-Heterocyclic Olefins in DMSO: An Effective Way to Evaluate the Stability of NHO-CO 2 Adducts. J Org Chem 2020; 85:13204-13210. [PMID: 32900190 DOI: 10.1021/acs.joc.0c01987] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A Brönsted basicity scale (∼24 pK units) for 85 commonly seen imidazole-, imidazoline-, triazole-, and thiazole-based N-heterocyclic olefins (NHOs) in DMSO was established using a well-examined computational model. The influence of substituents on the Brönsted basicities of these NHOs was investigated through basicity comparisons and rationalized by geometric analyses. The Gibbs energy (ΔGr) of the reaction between NHO and CO2 was also calculated, which linearly correlates with the basicity of the corresponding NHO, suggesting that the stability of NHO-CO2 adducts can be evaluated by the basicity of NHOs and a stronger basicity leads to a more stable NHO-CO2 adduct.
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Affiliation(s)
- Zhen Wang
- Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China
| | - Qian-Hang Niu
- Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China
| | - Xiao-Song Xue
- Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China.,State Key Laboratory on Elemento-Organic Chemistry, Department of Chemistry, Nankai University, Tianjin 300071, China
| | - Pengju Ji
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
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11
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Brehm M, Radicke J, Pulst M, Shaabani F, Sebastiani D, Kressler J. Dissolving Cellulose in 1,2,3-Triazolium- and Imidazolium-Based Ionic Liquids with Aromatic Anions. Molecules 2020; 25:E3539. [PMID: 32748878 PMCID: PMC7435399 DOI: 10.3390/molecules25153539] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 11/16/2022] Open
Abstract
We present 1,2,3-triazolium- and imidazolium-based ionic liquids (ILs) with aromatic anions as a new class of cellulose solvents. The two anions in our study, benzoate and salicylate, possess a lower basicity when compared to acetate and therefore should lead to a lower amount of N-heterocyclic carbenes (NHCs) in the ILs. We characterize their physicochemical properties and find that all of them are liquids at room temperature. By applying force field molecular dynamics (MD) simulations, we investigate the structure and dynamics of the liquids and find strong and long-lived hydrogen bonds, as well as significant π-π stacking between the aromatic anion and cation. Our ILs dissolve up to 8.5 wt.-% cellulose. Via NMR spectroscopy of the solution, we rule out chain degradation or derivatization, even after several weeks at elevated temperature. Based on our MD simulations, we estimate the enthalpy of solvation and derive a simple model for semi-quantitative prediction of cellulose solubility in ILs. With the help of Sankey diagrams, we illustrate the hydrogen bond network topology of the solutions, which is characterized by competing hydrogen bond donors and acceptors. The hydrogen bonds between cellulose and the anions possess average lifetimes in the nanosecond range, which is longer than found in common pure ILs.
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Affiliation(s)
- Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Julian Radicke
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Martin Pulst
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Farzaneh Shaabani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Daniel Sebastiani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Jörg Kressler
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
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12
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Delaude L. The Chemistry of Azolium‐Carboxylate Zwitterions and Related Compounds: a Survey of the Years 2009–2020. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000639] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Lionel Delaude
- Laboratory of CatalysisMolSys Research UnitInstitut de Chimie Organique (B6a)Université de Liège Allée du six Août 13 4000 Liège Belgium
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13
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Logdi R, Bag A, Tiwari AK. DFT based engineering of N-heterocyclic carbenes to exacerbate its activity for SO2 fixation and storage. J Mol Graph Model 2019; 93:107437. [DOI: 10.1016/j.jmgm.2019.08.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/13/2019] [Accepted: 08/16/2019] [Indexed: 01/01/2023]
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14
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Naumann S. Synthesis, properties & applications of N-heterocyclic olefins in catalysis. Chem Commun (Camb) 2019; 55:11658-11670. [PMID: 31517349 DOI: 10.1039/c9cc06316a] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N-Heterocyclic olefins (NHOs), a recently (re-)discovered type of electron-rich, polar alkene, are comprehensively presented. Along with synthetic aspects and chemical properties, special emphasis is put on the multi-faceted impact NHOs already have had on catalysis. This is discussed along the lines of small molecule organocatalysis, organo- and metal-assisted polymerization and of the understanding and application of NHO-ligated organometallic complexes. Highlighted are the strong basicity of NHOs ("superbases"), their high nucleophilicity and the design principles to tailor NHO (organo-)catalysts. It is demonstrated that NHOs can complement, and in many cases out-perform, the much better established N-heterocyclic carbene-based systems. Examples include among others CO2-sequestration, the polymerization of lactones and epoxides or the transfer hydrogenation of carbonyls. Further, the unique ability to selectively address basic or nucleophilic reaction pathways via NHO-mediation is detailed, as is the bonding situation in NHO-metal complexes and the ability of the olefin to act as an electronically flexible ligand.
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Affiliation(s)
- Stefan Naumann
- University of Stuttgart, Institute of Polymer Chemistry, 70569 Stuttgart, Germany.
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15
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Fu HC, You F, Li HR, He LN. CO 2 Capture and in situ Catalytic Transformation. Front Chem 2019; 7:525. [PMID: 31396509 PMCID: PMC6667559 DOI: 10.3389/fchem.2019.00525] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 07/09/2019] [Indexed: 11/22/2022] Open
Abstract
The escalating rate of fossil fuel combustion contributes to excessive CO2 emission and the resulting global climate change has drawn considerable attention. Therefore, tremendous efforts have been devoted to mitigate the CO2 accumulation in the atmosphere. Carbon capture and storage (CCS) strategy has been regarded as one of the promising options for controlling CO2 build-up. However, desorption and compression of CO2 need extra energy input. To circumvent this energy issue, carbon capture and utilization (CCU) strategy has been proposed whereby CO2 can be captured and in situ activated simultaneously to participate in the subsequent conversion under mild conditions, offering valuable compounds. As an alternative to CCS, the CCU has attracted much concern. Although various absorbents have been developed for the CCU strategy, the direct, in situ chemical conversion of the captured CO2 into valuable chemicals remains in its infancies compared with the gaseous CO2 conversion. This review summarizes the recent progress on CO2 capture and in situ catalytic transformation. The contents are introduced according to the absorbent types, in which different reaction type is involved and the transformation mechanism of the captured CO2 and the role of the absorbent in the conversion are especially elucidated. We hope this review can shed light on the transformation of the captured CO2 and arouse broad concern on the CCU strategy.
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Affiliation(s)
- Hong-Chen Fu
- College of Pharmacy, Nankai University, Tianjin, China.,State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
| | - Fei You
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
| | - Hong-Ru Li
- College of Pharmacy, Nankai University, Tianjin, China.,State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
| | - Liang-Nian He
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
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16
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Harloff J, Schulz A, Stoer P, Villinger A. Pseudo Halide Chemistry in Ionic Liquids with Decomposable Anions. Z Anorg Allg Chem 2019. [DOI: 10.1002/zaac.201900055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jörg Harloff
- Institut für Chemie; Universität Rostock; Albert-Einstein-Str. 3a 18059 Rostock Germany
| | - Axel Schulz
- Institut für Chemie; Universität Rostock; Albert-Einstein-Str. 3a 18059 Rostock Germany
- Abteilung Materialdesign; Leibniz-Institut für Katalyse e.V. an der Universität Rostock; Albert-Einstein-Str. 29a 18059 Rostock Germany
| | - Philip Stoer
- Institut für Chemie; Universität Rostock; Albert-Einstein-Str. 3a 18059 Rostock Germany
| | - Alexander Villinger
- Institut für Chemie; Universität Rostock; Albert-Einstein-Str. 3a 18059 Rostock Germany
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17
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Geeson MB, Ríos P, Transue WJ, Cummins CC. Orthophosphate and Sulfate Utilization for C-E (E = P, S) Bond Formation via Trichlorosilyl Phosphide and Sulfide Anions. J Am Chem Soc 2019; 141:6375-6384. [PMID: 30901207 DOI: 10.1021/jacs.9b01475] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reduction of phosphoric acid (H3PO4) or tetra- n-butylammonium bisulfate ([TBA][HSO4]) with trichlorosilane leads to the formation of the bis(trichlorosilyl)phosphide ([P(SiCl3)2]-, 1) and trichlorosilylsulfide ([Cl3SiS]-, 2) anions, respectively. Balanced equations for the formation of the TBA salts of anions 1 and 2 were formulated based on the identification of hexachlorodisiloxane and hydrogen gas as byproducts arising from these reductive processes: i) [H2PO4]- + 10HSiCl3 → 1 + 4O(SiCl3)2 + 6H2 for P and ii) [HSO4]- + 9HSiCl3 → 2 + 4O(SiCl3)2 + 5H2 for S. Hydrogen gas was identified by its subsequent use to hydrogenate an alkene ((-)-terpinen-4-ol) using Crabtree's catalyst ([(COD)Ir(py)(PCy3)][PF6], COD = 1,5-cyclooctadiene, py = pyridine, Cy = cyclohexyl). Phosphide 1 was generated in situ by the reaction of phosphoric acid and trichlorosilane and used to convert an alkyl chloride (1-chlorooctane) to the corresponding primary phosphine, which was isolated in 41% yield. Anion 1 was also prepared from [TBA][H2PO4] and isolated in 62% yield on a gram scale. Treatment of [TBA]1 with an excess of benzyl chloride leads to the formation of tetrabenzylphosphonium chloride, which was isolated in 61% yield. Sulfide 2 was used as a thionation reagent, converting benzophenone to thiobenzophenone in 62% yield. It also converted benzyl bromide to benzyl mercaptan in 55% yield. The TBA salt of trimetaphosphate ([TBA]3[P3O9]·2H2O), also a precursor to anion 1, was found to react with either trichlorosilane or silicon(IV) chloride to provide bis(trimetaphosphate)silicate, [TBA]2[Si(P3O9)2], characterized by NMR spectroscopy, X-ray crystallography, and elemental analysis. Trichlorosilane reduction of [TBA]2[Si(P3O9)2] also provided anion 1. The electronic structures of 1 and 2 were investigated using a suite of theoretical methods; the computational studies suggest that the trichlorosilyl ligand is a good π-acceptor and forms σ-bonds with a high degree of s character.
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Affiliation(s)
- Michael B Geeson
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Pablo Ríos
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Wesley J Transue
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Christopher C Cummins
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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Peixoto D, Malta G, Cruz H, Barroso S, Carvalho AL, Ferreira LM, Branco PS. N-Heterocyclic Olefin Catalysis for the Ring Opening of Cyclic Amidine Compounds: A Pathway to the Synthesis of ε-Caprolactam- and γ-Lactam-Derived Amines. J Org Chem 2019; 84:3793-3800. [PMID: 30753075 DOI: 10.1021/acs.joc.8b02823] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
For the first time, 1,2-dimethyl-3-ethylimidazolium iodide (1a) catalyzes the ring opening of the bicyclic amidine system of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) or DBN (1,5-diazabicyclo[4.3.0]non-5-ene) on reaction with aldehydes. The mechanism here proposed involves an N-heterocyclic olefin (NHO) catalytic species that acts as a nucleophile to promote the cyclic amidine ring opening. The resulting ε-caprolactam- and γ-lactam-derived imines were obtained in moderate to excellent yields (28-99%) and reduced to the corresponding amines by sodium borohydride. Confirmation of the imine product was achieved via single-crystal X-ray diffraction studies.
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19
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Brehm M, Pulst M, Kressler J, Sebastiani D. Triazolium-Based Ionic Liquids: A Novel Class of Cellulose Solvents. J Phys Chem B 2019; 123:3994-4003. [DOI: 10.1021/acs.jpcb.8b12082] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Martin Pulst
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Jörg Kressler
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Daniel Sebastiani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
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20
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Schuldt R, Kästner J, Naumann S. Proton Affinities of N-Heterocyclic Olefins and Their Implications for Organocatalyst Design. J Org Chem 2019; 84:2209-2218. [DOI: 10.1021/acs.joc.8b03202] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Robin Schuldt
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Johannes Kästner
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Stefan Naumann
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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21
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Guschlbauer J, Vollgraff T, Sundermeyer J. Systematic study on anion–cation interactions via doubly ionic H-bonds in 1,3-dimethylimidazolium salts comprising chalcogenolate anions MMIm [ER] (E = S, Se; R = H, tBu, SiMe3). Dalton Trans 2019; 48:10971-10978. [DOI: 10.1039/c9dt01586h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We present convenient syntheses of so far inaccessible, crystalline and highly pure 1,3-dialkylimidazolium salts with extremely nucleophilic thiolate and selenolate anions [ER]− (R = H, tBu, SiMe3).
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Affiliation(s)
- Jannick Guschlbauer
- Fachbereich Chemie and Materials Science Center
- Philipps-Universität Marburg
- 35043 Marburg
- Germany
| | - Tobias Vollgraff
- Fachbereich Chemie and Materials Science Center
- Philipps-Universität Marburg
- 35043 Marburg
- Germany
| | - Jörg Sundermeyer
- Fachbereich Chemie and Materials Science Center
- Philipps-Universität Marburg
- 35043 Marburg
- Germany
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22
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Nesterov V, Reiter D, Bag P, Frisch P, Holzner R, Porzelt A, Inoue S. NHCs in Main Group Chemistry. Chem Rev 2018; 118:9678-9842. [PMID: 29969239 DOI: 10.1021/acs.chemrev.8b00079] [Citation(s) in RCA: 508] [Impact Index Per Article: 84.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Since the discovery of the first stable N-heterocyclic carbene (NHC) in the beginning of the 1990s, these divalent carbon species have become a common and available class of compounds, which have found numerous applications in academic and industrial research. Their important role as two-electron donor ligands, especially in transition metal chemistry and catalysis, is difficult to overestimate. In the past decade, there has been tremendous research attention given to the chemistry of low-coordinate main group element compounds. Significant progress has been achieved in stabilization and isolation of such species as Lewis acid/base adducts with highly tunable NHC ligands. This has allowed investigation of numerous novel types of compounds with unique electronic structures and opened new opportunities in the rational design of novel organic catalysts and materials. This Review gives a general overview of this research, basic synthetic approaches, key features of NHC-main group element adducts, and might be useful for the broad research community.
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Affiliation(s)
- Vitaly Nesterov
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Dominik Reiter
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Prasenjit Bag
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Philipp Frisch
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Richard Holzner
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Amelie Porzelt
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
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23
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Feroci M, Chiarotto I, Orsini M, Pandolfi F, Zane D, Inesi A. Electrogenerated N-Heterocyclic Olefins: Stability and Catalytic Ability. ChemElectroChem 2017. [DOI: 10.1002/celc.201700992] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marta Feroci
- Dept. Fundamental and Applied Sciences for Engineering (SBAI); Sapienza University of Rome; via Castro Laurenziano, 7 00161 Rome Italy
| | - Isabella Chiarotto
- Dept. Fundamental and Applied Sciences for Engineering (SBAI); Sapienza University of Rome; via Castro Laurenziano, 7 00161 Rome Italy
| | - Monica Orsini
- Dept. of Engineering; Università RomaTre; via V. Volterra, 62 00146 Rome Italy
| | - Fabiana Pandolfi
- Dept. Fundamental and Applied Sciences for Engineering (SBAI); Sapienza University of Rome; via Castro Laurenziano, 7 00161 Rome Italy
| | - Daniela Zane
- CNR SMN Istituto per lo Studio dei Materiali Nanostrutturati UOS Sapienza; Via del Castro Laurenziano 7 00161 Roma Italy
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24
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Walther P, Naumann S. N-Heterocyclic Olefin-Based (Co)polymerization of a Challenging Monomer: Homopolymerization of ω-Pentadecalactone and Its Copolymers with γ-Butyrolactone, δ-Valerolactone, and ε-Caprolactone. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01678] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Patrick Walther
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Stefan Naumann
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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