1
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Šegina J, Ciber L, Brodnik H, Požgan F, Svete J, Štefane B, Grošelj U. Synthesis of Six-Membered N-Heterocyclic Carbene Precursors Based on Camphor. Molecules 2023; 28:7973. [PMID: 38138463 PMCID: PMC10745536 DOI: 10.3390/molecules28247973] [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: 11/13/2023] [Revised: 11/29/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
The endo- and exo-N-heterocyclic carbene precursors based on camphor were prepared diastereoselectively in five synthetic steps starting from (1S)-(+)-ketopinic acid. The obtained N-heterocyclic carbene precursors were investigated in an asymmetric benzoin reaction. All new compounds were fully characterized, and the absolute configurations were determined via X-ray diffraction and NOESY measurements.
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Affiliation(s)
| | | | | | | | | | | | - Uroš Grošelj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, 1000 Ljubljana, Slovenia; (J.Š.); (L.C.); (F.P.); (J.S.); (B.Š.)
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2
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Yang S, Zhou T, Yu X, Szostak M. Ag-NHC Complexes in the π-Activation of Alkynes. Molecules 2023; 28:molecules28030950. [PMID: 36770617 PMCID: PMC9920927 DOI: 10.3390/molecules28030950] [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: 12/30/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Silver-NHC (NHC = N-heterocyclic carbene) complexes play a special role in the field of transition-metal complexes due to (1) their prominent biological activity, and (2) their critical role as transfer reagents for the synthesis of metal-NHC complexes by transmetalation. However, the application of silver-NHCs in catalysis is underdeveloped, particularly when compared to their group 11 counterparts, gold-NHCs (Au-NHC) and copper-NHCs (Cu-NHC). In this Special Issue on Featured Reviews in Organometallic Chemistry, we present a comprehensive overview of the application of silver-NHC complexes in the p-activation of alkynes. The functionalization of alkynes is one of the most important processes in chemistry, and it is at the bedrock of organic synthesis. Recent studies show the significant promise of silver-NHC complexes as unique and highly selective catalysts in this class of reactions. The review covers p-activation reactions catalyzed by Ag-NHCs since 2005 (the first example of p-activation in catalysis by Ag-NHCs) through December 2022. The review focuses on the structure of NHC ligands and p-functionalization methods, covering the following broadly defined topics: (1) intramolecular cyclizations; (2) CO2 fixation; and (3) hydrofunctionalization reactions. By discussing the role of Ag-NHC complexes in the p-functionalization of alkynes, the reader is provided with an overview of this important area of research and the role of Ag-NHCs to promote reactions that are beyond other group 11 metal-NHC complexes.
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3
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Structural effect of imidazolium salts on electrochemical conversion of carbon dioxide to imidazolium carboxylate. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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4
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Cyclic (alkyl)(amino)carbene (CAAC) ligands: Electronic structure and application as chemically- and redox-non-innocent ligands and chromophores. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2022. [DOI: 10.1016/bs.adomc.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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5
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Vermersch F, Yazdani S, Junor GP, Grotjahn DB, Jazzar R, Bertrand G. Stable Singlet Carbenes as Organic Superbases. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111588] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- François Vermersch
- UCSD-CNRS Joint Research Laboratory (IRL 3555) Department of Chemistry and Biochemistry University of California San Diego, La Jolla CA 92093-0358 USA
| | - Sima Yazdani
- UCSD-CNRS Joint Research Laboratory (IRL 3555) Department of Chemistry and Biochemistry University of California San Diego, La Jolla CA 92093-0358 USA
- Department of Chemistry and Biochemistry San Diego State University 5500 Campanile Drive San Diego CA 92182-1030 USA
| | - Glen P. Junor
- UCSD-CNRS Joint Research Laboratory (IRL 3555) Department of Chemistry and Biochemistry University of California San Diego, La Jolla CA 92093-0358 USA
| | - Douglas B. Grotjahn
- Department of Chemistry and Biochemistry San Diego State University 5500 Campanile Drive San Diego CA 92182-1030 USA
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Laboratory (IRL 3555) Department of Chemistry and Biochemistry University of California San Diego, La Jolla CA 92093-0358 USA
| | - Guy Bertrand
- UCSD-CNRS Joint Research Laboratory (IRL 3555) Department of Chemistry and Biochemistry University of California San Diego, La Jolla CA 92093-0358 USA
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6
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Vermersch F, Yazdani S, Junor GP, Grotjahn DB, Jazzar R, Bertrand G. Stable Singlet Carbenes as Organic Superbases. Angew Chem Int Ed Engl 2021; 60:27253-27257. [PMID: 34729888 DOI: 10.1002/anie.202111588] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/18/2021] [Indexed: 11/10/2022]
Abstract
A simple experimental procedure for scaling carbene Brønsted basicity is described. The results highlight the strong basicity of pyrazol-4-ylidenes, a type of mesoionic carbene, also named cyclic-bentallenes (CBA). They are more basic (pKaH >42.7 in acetonitrile) than the popular proazaphosphatrane Verkade bases, and even the Schwesinger phosphazene superbase P4 (t Bu). The basicity of these compounds can readily be tuned, and they are accessible in multigram quantities. These results open new avenues for carbon centered superbases.
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Affiliation(s)
- François Vermersch
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
| | - Sima Yazdani
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA.,Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA
| | - Glen P Junor
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
| | - Douglas B Grotjahn
- Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
| | - Guy Bertrand
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
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7
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Diniz Lessa M, Fajardo JRD, Delarmelina M, Carneiro JWDM. A DFT study on the mechanism for polymerization of δ-valerolactone initiated by N-heterocyclic carbene (NHC) catalysts. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2021.111896] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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8
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Vemulapalli S, Guest M, Smajlagic I, Dudding T. p Ka Scale for Cyclopropenium Ions with Applications in CO 2 Capture. J Org Chem 2021; 86:11835-11844. [PMID: 34369775 DOI: 10.1021/acs.joc.1c01255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular acid-base properties are core to understanding chemical systems and the prediction of reactivity. This axiom holds for cyclopropenium ions in terms of their broad use as (organo)catalysts, ligands, redox-flow batteries, and applications in materials sciences. In view of this significant status, and with it, the critical importance of acidity, we disclose in this report the first comprehensive computational study of the pKa values of cyclopropenium ions employing a subset of 70 structurally diverse cyclopropenium derivatives, density functional computations, and Hammett linear free-energy relationships. Capitalizing upon these computed findings, and with an eye toward greenhouse gas trapping, we further document the timely use of a cyclopropenium-cyclopropenylidene coupled platform for CO2 capture and light-triggered release.
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Affiliation(s)
- Srini Vemulapalli
- Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Matt Guest
- Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Ivor Smajlagic
- Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Travis Dudding
- Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
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9
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Kureja K, Zinke J, Bruhn C, Siemeling U. Homodinuclear Rh
I
and Ir
I
Complexes Derived from Imidazolium‐Benzimidazolates. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202000394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Kunal Kureja
- Institute of Chemistry University of Kassel Heinrich-Plett-Str. 40 34132 Kassel Germany
| | - Julian Zinke
- Institute of Chemistry University of Kassel Heinrich-Plett-Str. 40 34132 Kassel Germany
| | - Clemens Bruhn
- Institute of Chemistry University of Kassel Heinrich-Plett-Str. 40 34132 Kassel Germany
| | - Ulrich Siemeling
- Institute of Chemistry University of Kassel Heinrich-Plett-Str. 40 34132 Kassel Germany
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10
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Mazars F, Hrubaru M, Tumanov N, Wouters J, Delaude L. Synthesis of Azolium‐2‐dithiocarboxylate Zwitterions under Mild, Aerobic Conditions. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100274] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- François Mazars
- Laboratory of Catalysis MolSys Research Unit Université de Liège Institut de Chimie Organique (B6a) Allée du six Août 13 4000 Liège Belgium
| | - Madalina Hrubaru
- Center for Organic Chemistry “Costin D. Nenitescu” Romanian Academy Spl Independentei Bucureşti, 202B 060023 Bucharest Romania
| | - Nikolay Tumanov
- Department of Chemistry Université de Namur Rue de Bruxelles 61 5000 Namur Belgium
| | - Johan Wouters
- Department of Chemistry Université de Namur Rue de Bruxelles 61 5000 Namur Belgium
| | - Lionel Delaude
- Laboratory of Catalysis MolSys Research Unit Université de Liège Institut de Chimie Organique (B6a) Allée du six Août 13 4000 Liège Belgium
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11
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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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12
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Benedikter MJ, Musso JV, Frey W, Schowner R, Buchmeiser MR. Cationic Group VI Metal Imido Alkylidene
N
‐Heterocyclic Carbene Nitrile Complexes: Bench‐Stable, Functional‐Group‐Tolerant Olefin Metathesis Catalysts. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Mathis J. Benedikter
- Institut für Polymerchemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Janis V. Musso
- Institut für Polymerchemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Wolfgang Frey
- Institut für Organische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Roman Schowner
- Institut für Polymerchemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Michael R. Buchmeiser
- Institut für Polymerchemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
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13
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Benedikter MJ, Musso JV, Frey W, Schowner R, Buchmeiser MR. Cationic Group VI Metal Imido Alkylidene N-Heterocyclic Carbene Nitrile Complexes: Bench-Stable, Functional-Group-Tolerant Olefin Metathesis Catalysts. Angew Chem Int Ed Engl 2020; 60:1374-1382. [PMID: 33009884 PMCID: PMC7839548 DOI: 10.1002/anie.202011666] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/01/2020] [Indexed: 11/08/2022]
Abstract
Despite their excellent selectivities and activities, Mo‐and W‐based catalysts for olefin metathesis have not gained the same widespread use as Ru‐based systems, mainly due to their inherent air sensitivity. Herein, we describe the synthesis of air‐stable cationic‐at‐metal molybdenum and tungsten imido alkylidene NHC nitrile complexes. They catalyze olefin metathesis reactions of substrates containing functional groups such as (thio‐) esters, (thio‐) ethers and alcohols without the need for prior activation, for example, by a Lewis acid. The presence of a nitrile ligand was found to be essential for their stability towards air, while no decrease in activity and productivity could be observed upon coordination of a nitrile. Variations of the imido and anionic ligand revealed that alkoxide complexes with electron‐withdrawing imido ligands offer the highest reactivities and excellent stability compared to analogous triflate and halide complexes.
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Affiliation(s)
- Mathis J Benedikter
- Institut für Polymerchemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Janis V Musso
- Institut für Polymerchemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Wolfgang Frey
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Roman Schowner
- Institut für Polymerchemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Michael R Buchmeiser
- Institut für Polymerchemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
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14
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Kinney ZJ, Rheingold AL, Protasiewicz JD. Preferential N-H⋯:C[double bond splayed right] hydrogen bonding involving ditopic NH-containing systems and N-heterocyclic carbenes. RSC Adv 2020; 10:42164-42171. [PMID: 35516763 PMCID: PMC9057831 DOI: 10.1039/d0ra08490e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 11/05/2020] [Indexed: 11/21/2022] Open
Abstract
Hydrogen bonding plays a critical role in maintaining order and structure in complex biological and synthetic systems. N-heterocyclic carbenes (NHCs) represent one of the most versatile tools in the synthetic chemistry toolbox, yet their potential as neutral carbon hydrogen bond acceptors remains underexplored. This report investigates this capability in a strategic manner, wherein carbene-based hydrogen bonding can be assessed by use of ditopic NH-containing molecules. N-H bonds are unique as there are three established reaction modes with carbenes: non-traditional hydrogen bonding adducts (X-H⋯:C[double bond splayed right]), salts arising from proton transfer ([H-C[double bond splayed right]]+[X]-), or amines from insertion of the carbene into the N-H bond. Yet, there are no established rules to predict product distributions or the strength of these associations. Here we seek to correlate the hydrogen bond strength of symmetric and asymmetric ditopic secondary amines with 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr, a representative NHC). In symmetric and asymmetric ditopic amine adducts both the solid-state (hydrogen bond lengths, NHC interior angles) and solution-state (1H Δδ of NH signals, 13C signals of carbenic carbon) can be related to the pK a of the parent amine.
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Affiliation(s)
- Zacharias J Kinney
- Department of Chemistry, Case Western Reserve University Cleveland Ohio 44106 USA
| | - Arnold L Rheingold
- Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093 USA
| | - John D Protasiewicz
- Department of Chemistry, Case Western Reserve University Cleveland Ohio 44106 USA
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15
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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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16
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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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17
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Konstandaras N, Dunn MH, Luis ET, Cole ML, Harper JB. The pK a values of N-aryl imidazolinium salts, their higher homologues, and formamidinium salts in dimethyl sulfoxide. Org Biomol Chem 2020; 18:1910-1917. [PMID: 32095802 DOI: 10.1039/d0ob00036a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A series of imidazolinium salts, their six-, seven- and eight-membered homologues, and the related formamidinium salts were prepared, and their pKa values were determined in DMSO at 25 °C using the bracketing indicator method. The effect of each type of structural variation on the acidity of each salt was considered, particularly noting the importance of ring size and the effect of the steric and electronic nature of the N-aryl substituents. The effect of a cyclic structure was also probed through comparing the cyclic systems with the corresponding formamidinium salts, noting the importance of conformational flexibility in the latter cases. Along with allowing choice of appropriate bases for deprotonation of these species, it is anticipated that the data presented will aid in the understanding of the nucleophilicity, and potentially catalytic efficacy, of the corresponding carbenes.
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Affiliation(s)
- Nicholas Konstandaras
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Michelle H Dunn
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Ena T Luis
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Marcus L Cole
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Jason B Harper
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
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