1
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Hoffmann G, Guégan F, Labet V, Joubert L, Chermette H, Morell C, Tognetti V. Expanding horizons in conceptual density functional theory: Novel ensembles and descriptors to decipher reactivity patterns. J Comput Chem 2024; 45:1716-1726. [PMID: 38580454 DOI: 10.1002/jcc.27363] [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: 10/20/2023] [Revised: 02/16/2024] [Accepted: 02/22/2024] [Indexed: 04/07/2024]
Abstract
Conceptual density functional theory (CDFT) and the quantum reactivity descriptors stemming from it have proven to be valuable tools for understanding the chemical behavior of molecules. This article is presented as being intrinsically of dual character. In a first part, it briefly reviews, in a deliberately didactical way, the main ensembles in CDFT, while the second half presents two additional ensembles, where the chemical hardness acts as a natural variable, and their respective reactivity descriptors. The evaluation of these reactivity descriptors on common organic chemical reagents are presented and discussed.
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Affiliation(s)
- Guillaume Hoffmann
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Villeurbanne, France
| | - Frédéric Guégan
- IC2MP UMR 7285, Université de Poitiers - CNRS, Poitiers, France
| | - Vanessa Labet
- Sorbonne Université CNRS, MONARIS, UMR8233, Paris, France
| | - Laurent Joubert
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, Rouen, France
| | - Henry Chermette
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Villeurbanne, France
| | - Christophe Morell
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Villeurbanne, France
| | - Vincent Tognetti
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, Rouen, France
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2
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Eckhoff M, Diedrich JV, Mücke M, Proppe J. Quantitative Structure-Reactivity Relationships for Synthesis Planning: The Benzhydrylium Case. J Phys Chem A 2024; 128:343-354. [PMID: 38113457 PMCID: PMC10788916 DOI: 10.1021/acs.jpca.3c07289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 11/28/2023] [Accepted: 12/01/2023] [Indexed: 12/21/2023]
Abstract
Selective and feasible reactions are among the top targets in synthesis planning. Mayr's approach to quantifying chemical reactivity has greatly facilitated the planning process, but reactivity parameters for new compounds require time-consuming experiments. In the past decade, data-driven modeling has been gaining momentum in the field, as it shows promise in terms of efficient reactivity prediction. However, state-of-the-art models use quantum chemical data as input, which prevent access to real-time planning in organic synthesis. Here, we present a novel data-driven workflow for predicting reactivity parameters of molecules that takes only structural information as input, enabling de facto real-time reactivity predictions. We use the well-understood chemical space of benzhydrylium ions as an example to demonstrate the functionality of our approach and the performance of the resulting quantitative structure-reactivity relationships (QSRRs). Our results suggest that it is straightforward to build low-cost QSRR models that are accurate, interpretable, and transferable to unexplored systems within a given scope of application. Moreover, our QSRR approach suggests that Hammett σ parameters are only approximately additive.
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Affiliation(s)
- Maike Eckhoff
- Institute
of Physical and Theoretical Chemistry, TU
Braunschweig, Braunschweig 38106, Germany
| | - Johannes V. Diedrich
- Institute
of Physical and Theoretical Chemistry, TU
Braunschweig, Braunschweig 38106, Germany
- Institute
of Physical Chemistry, University of Göttingen, Göttingen 37077, Germany
| | - Maike Mücke
- Institute
of Physical and Theoretical Chemistry, TU
Braunschweig, Braunschweig 38106, Germany
- Institute
of Physical Chemistry, University of Göttingen, Göttingen 37077, Germany
| | - Jonny Proppe
- Institute
of Physical and Theoretical Chemistry, TU
Braunschweig, Braunschweig 38106, Germany
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3
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Martínez AG, Siehl HU, de la Moya S, Gómez PC. Easy and accurate computation of energy barriers for carbocation solvation: an expeditious tool to face carbocation chemistry. Phys Chem Chem Phys 2023; 25:31012-31019. [PMID: 37938916 DOI: 10.1039/d3cp03544a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
An expeditious procedure for the challenging computation of the free energy barriers (ΔG≠) for the solvation of carbocations is presented. This procedure is based on Marcus Theory (MT) and the popular B3LYP/6-31G(d)//PCM method, and it allows the easy, accurate and inexpensive prediction of these barriers for carbocations of very different stability. This method was validated by the fair mean absolute error (ca. 1.5 kcal mol-1) achieved in the prediction of 19 known experimental barriers covering a range of ca. 50 kcal mol-1. Interestingly, the new procedure also uses an original method for the calculation of the required inner reorganization energy (Λi) and free energy of reaction (ΔG). This procedure should pave the way to face computationally the pivotal issue of carbocation chemistry and could be easily extended to any bimolecular organic reaction.
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Affiliation(s)
- Antonio G Martínez
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Madrid, Spain.
| | - Hans-Ulrich Siehl
- Abteilung Organische Chemie I, Universität Ulm, Albert Einstein Alee 11, 89069 Ulm, Germany
| | - Santiago de la Moya
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Madrid, Spain.
| | - Pedro C Gómez
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Madrid, Spain.
- Departamento de Química Física, Universidad Complutense de Madrid, Facultad de Ciencias Químicas, 28040 Madrid, Spain.
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4
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Weser O, Hein-Janke B, Mata RA. Automated handling of complex chemical structures in Z-matrix coordinates-The chemcoord library. J Comput Chem 2023; 44:710-726. [PMID: 36541725 DOI: 10.1002/jcc.27029] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 10/05/2022] [Accepted: 10/09/2022] [Indexed: 12/24/2022]
Abstract
In this work, we present a fully automated method for the construction of chemically meaningful sets of hierarchical nonredundant internal coordinates (ICs; also commonly denoted as Z-matrices) from the Cartesian coordinates of a molecular system. Particular focus is placed on avoiding ill-definitions of angles and dihedrals due to linear arrangements of atoms, to consistently guarantee a well-defined transformation to Cartesian coordinates, even after structural changes. The representations thus obtained are particularly well suited for pathway construction in double-ended methods for transition state search and optimizations with nonlinear constraints. Analytical gradients for the transformation between the coordinate systems were derived for analytical geometry optimizations purely in Z-matrix coordinates. The geometry optimization was coupled with a Symbolic Algebra package to support arbitrary nonlinear constraints in Z-matrix coordinates, while retaining analytical energy gradient conversion. The difference to the commonly used nonhierarchical IC transformations is discussed. Sample applications are provided for a number of common chemical reactions and illustrative examples.
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Affiliation(s)
- Oskar Weser
- Electronic Structure Theory Department, Max-Planck-Institute for Solid State Research, Stuttgart, Germany.,Institute of Physical Chemistry, University of Goettingen, Goettingen, Germany
| | - Björn Hein-Janke
- Institute of Physical Chemistry, University of Goettingen, Goettingen, Germany
| | - Ricardo A Mata
- Institute of Physical Chemistry, University of Goettingen, Goettingen, Germany
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5
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Gupta R, Csókás D, Lye K, Young RD. Experimental and computational insights into the mechanism of FLP mediated selective C-F bond activation. Chem Sci 2023; 14:1291-1300. [PMID: 36756325 PMCID: PMC9891352 DOI: 10.1039/d2sc05632a] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 01/05/2023] [Indexed: 01/15/2023] Open
Abstract
Frustrated Lewis pairs (FLP) comprising of B(C6F5)3 (BCF) and 2,4,6-triphenylpyridine (TPPy), P(o-Tol)3 or tetrahydrothiophene (THT) have been shown to mediate selective C-F activation in both geminal and chemically equivalent distal C-F sites. In comparison to other reported attempts of C-F activation using BCF, these reactions appear surprisingly facile. We investigate this reaction through a combination of experimental and computational chemistry to understand the mechanism of the initial C-F activation event and the origin of the selectivity that prevents subsequent C-F activation in the monoactivated salts. We find that C-F activation likely occurs via a Lewis acid assisted SN1 type pathway as opposed to a concerted FLP pathway (although the use of an FLP is important to elevate the ground state energy), where BCF is sufficiently Lewis acidic to overcome the kinetic barrier for C-F activation in benzotrifluorides. The resultant intermediate salts of the form [ArCF2(LB)][BF(C6F5)3] (LB = Lewis base) are relatively thermodynamically unstable, and an equilibrium operates between the fluorocarbon/FLP and their activation products. As such, the use of a fluoride sequestering reagent such as Me3SiNTf2 is key to the realisation of the forward C-F activation reaction in benzotrifluorides. Selectivity in this reaction can be attributed to both the installation of bulky Lewis bases geminal to residual C-F sites and from electronic re-ordering of kinetic barriers (of C-F sites in products and starting materials) arising from the electron withdrawing nature of the pyridinium, phosphonium and sulfonium groups.
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Affiliation(s)
- Richa Gupta
- Department of Chemistry, National University of Singapore 3 Science Drive 3 117543 Singapore
| | - Dániel Csókás
- Department of Chemistry, National University of Singapore 3 Science Drive 3 117543 Singapore
| | - Kenneth Lye
- Department of Chemistry, National University of Singapore 3 Science Drive 3 117543 Singapore
| | - Rowan D. Young
- Department of Chemistry, National University of Singapore3 Science Drive 3117543Singapore,School of Chemistry and Molecular Biosciences, The University of QueenslandSt Lucia, 4072QueenslandAustralia
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6
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Abstract
Reactivity scales are useful research tools for chemists, both experimental and computational. However, to determine the reactivity of a single molecule, multiple measurements need to be carried out, which is a time-consuming and resource-intensive task. In this Tutorial Review, we present alternative approaches for the efficient generation of quantitative structure-reactivity relationships that are based on quantum chemistry, supervised learning, and uncertainty quantification. First published in 2002, we observe a tendency for these relationships to become not only more predictive but also more interpretable over time.
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Affiliation(s)
- Maike Vahl
- Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany.
| | - Jonny Proppe
- Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany.
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7
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Desrosiers V, Knight SM, Fontaine FG. A Metal-Free Approach for the C–H Activation and Transfer Borylation of Electron-Rich Alkenes. ACS Catal 2022. [DOI: 10.1021/acscatal.2c04305] [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)
- Vincent Desrosiers
- Département de Chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, Quebec G1 V 0A6, Canada
| | - Samantha M. Knight
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, Halifax, Nova Scotia B3H 4R2, Canada
| | - Frédéric-Georges Fontaine
- Département de Chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, Quebec G1 V 0A6, Canada
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8
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Solvent effect, quantification and correlation analysis of the nucleophilicities of cyclic secondary amines. CHEMICAL PAPERS 2022. [DOI: 10.1007/s11696-022-02483-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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9
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When machine learning meets molecular synthesis. TRENDS IN CHEMISTRY 2022. [DOI: 10.1016/j.trechm.2022.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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10
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Proppe J, Kircher J. Uncertainty Quantification of Reactivity Scales. Chemphyschem 2022; 23:e202200061. [PMID: 35189024 PMCID: PMC9314972 DOI: 10.1002/cphc.202200061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/16/2022] [Indexed: 11/09/2022]
Abstract
According to Mayr, polar organic synthesis can be rationalized by a simple empirical relationship linking bimolecular rate constants to as few as three reactivity parameters. Here, we propose an extension to Mayr's reactivity method that is rooted in uncertainty quantification and transforms the reactivity parameters into probability distributions. Through uncertainty propagation, these distributions can be transformed into uncertainty estimates for bimolecular rate constants. Chemists can exploit these virtual error bars to enhance synthesis planning and to decrease the ambiguity of conclusions drawn from experimental data. We demonstrate the above at the example of the reference data set released by Mayr and co-workers [J. Am. Chem. Soc. 2001, 123, 9500; J. Am. Chem. Soc. 2012, 134, 13902]. As by-product of the new approach, we obtain revised reactivity parameters for 36 π-nucleophiles and 32 benzhydrylium ions.
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Affiliation(s)
- Jonny Proppe
- Technische Universität Braunschweig: Technische Universitat Braunschweig, Institute of Physical and Theoretical Chemistry, Gaußstraße 17, 38106, Braunschweig, GERMANY
| | - Johannes Kircher
- Georg-August-Universität Göttingen: Georg-August-Universitat Gottingen, Institute of Physical Chemistry, Tammannstraße 6, 37077, Göttingen, GERMANY
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11
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Krajewski AE, Lee JK. Nucleophilicity and Electrophilicity in the Gas Phase: Silane Hydricity. J Org Chem 2022; 87:1840-1849. [PMID: 35044778 DOI: 10.1021/acs.joc.1c02763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydricity is of great import as hydride transfer reactions are prominent in many processes, including organic synthesis, photoelectrocatalysis, and hydrogen activation. Herein, the kinetic hydricity of a series of silanes is examined in the gas phase. Most of these reactions have not heretofore been studied in vacuo and provide valuable data that can be compared to condensed-phase hydricity, to reveal the effects of solvent. Both experiments and computations are used to gain insight into mechanism and reactivity. In a broader sense, these studies also represent a first step toward systematically understanding nucleophilicity and electrophilicity in the absence of a solvent.
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Affiliation(s)
- Allison E Krajewski
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
| | - Jeehiun K Lee
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, United States
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12
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Rammah M, Mahdhaoui F, Ayachi S, Boubaker T. Exploring the reactivity of benzotriazole derivatives: Mayr's approach and density functional theory analysis. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.131310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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13
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Babu KN, Massarwe F, Shioukhi I, Masarwa A. Sequential Selective C-H and C(sp 3 )- + P Bond Functionalizations: An Entry to Bioactive Arylated Scaffolds. Angew Chem Int Ed Engl 2021; 60:26199-26209. [PMID: 34618394 DOI: 10.1002/anie.202111164] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Indexed: 12/14/2022]
Abstract
Organophosphonium salts containing C(sp3 )-+ P bonds are among the most utilized reagents in organic synthesis for constructing C-C double bonds. However, their use as C-selective electrophilic groups is rare. Here, we explore an efficient and general transition-metal-free method for sequential chemo- and regioselective C-H and C(sp3 )-+ P bond functionalizations. In the present study, C-H alkylation resulting in the synthesis of benzhydryl triarylphosphonium salts was achieved by one-pot, four-component cross-coupling reactions of simple and commercially available starting materials. The utility of the resulting phosphonium salt building blocks was demonstrated by the chemoselective post-functionalization of benzylic C(sp3 )-+ PPh3 groups to achieve aminations, thiolations, and arylations. In this way, benzhydrylamines, benzhydrylthioethers, and triarylmethanes, structural motifs that are present in many pharmaceuticals and agrochemicals, are readily accessed. These include the synthesis of two anticancer agents from simple materials in only two to three steps. Additionally, a protocol for late-stage functionalization of bioactive drugs has been developed using benzhydrylphosphonium salts. This new approach should provide novel transformations for application in both academic and pharmaceutical research.
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Affiliation(s)
- K Naresh Babu
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Fedaa Massarwe
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Israa Shioukhi
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Ahmad Masarwa
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
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14
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Babu KN, Massarwe F, Shioukhi I, Masarwa A. Sequential Selective C−H and C(sp
3
)−
+
P Bond Functionalizations: An Entry to Bioactive Arylated Scaffolds. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- K. Naresh Babu
- Institute of Chemistry The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | - Fedaa Massarwe
- Institute of Chemistry The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | - Israa Shioukhi
- Institute of Chemistry The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | - Ahmad Masarwa
- Institute of Chemistry The Hebrew University of Jerusalem Jerusalem 9190401 Israel
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15
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Hoshikawa S, Yanai H, Martín-Mejías I, Lázaro-Milla C, Aragoncillo C, Almendros P, Matsumoto T. Synthesis of Polycyclic Aromatic Hydrocarbons Decorated by Fluorinated Carbon Acids/Carbanions. Chemistry 2021; 27:16112-16116. [PMID: 34542205 DOI: 10.1002/chem.202103188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Indexed: 11/07/2022]
Abstract
The carboarylation reaction of biphenyl-alkynes was successfully triggered by electrophilic attack of 1,1-bis(triflyl)ethylene on the alkyne moiety to give polycyclic aromatic hydrocarbons (PAHs) decorated by superacidic carbon acid functionality. Neutralisation of thus obtained acids with NaHCO3 yielded the corresponding sodium salts, which showed improved solubility in both aqueous and organic solvents.
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Affiliation(s)
- Shoki Hoshikawa
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Hikaru Yanai
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Irene Martín-Mejías
- Instituto de Química Orgánica General, IQOG, Consejo Superior de Investigaciones Científicas, CSIC, Juan de la Cierva 3, 28006, Madrid, Spain
| | - Carlos Lázaro-Milla
- Grupo de Lactamas y Heterociclos Bioactivos, Unidad Asociada al CSIC, Departamento de Química Orgánica, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Cristina Aragoncillo
- Grupo de Lactamas y Heterociclos Bioactivos, Unidad Asociada al CSIC, Departamento de Química Orgánica, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Pedro Almendros
- Instituto de Química Orgánica General, IQOG, Consejo Superior de Investigaciones Científicas, CSIC, Juan de la Cierva 3, 28006, Madrid, Spain
| | - Takashi Matsumoto
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
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16
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Kobylarski M, Monsigny L, Thuéry P, Berthet JC, Cantat T. Uranyl(VI) Triflate as Catalyst for the Meerwein-Ponndorf-Verley Reaction. Inorg Chem 2021; 60:16140-16148. [PMID: 34647730 DOI: 10.1021/acs.inorgchem.1c01798] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Catalytic transformation of oxygenated compounds is challenging in f-element chemistry due to the high oxophilicity of the f-block metals. We report here the first Meerwein-Ponndorf-Verley (MPV) reduction of carbonyl substrates with uranium-based catalysts, in particular from a series of uranyl(VI) compounds where [UO2(OTf)2] (1) displays the greatest efficiency (OTf = trifluoromethanesulfonate). [UO2(OTf)2] reduces a series of aromatic and aliphatic aldehydes and ketones into their corresponding alcohols with moderate to excellent yields, using iPrOH as a solvent and a reductant. The reaction proceeds under mild conditions (80 °C) with an optimized catalytic charge of 2.3 mol % and KOiPr as a cocatalyst. The reduction of aldehydes (1-10 h) is faster than that of ketones (>15 h). NMR investigations clearly evidence the formation of hemiacetal intermediates with aldehydes, while they are not formed with ketones.
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Affiliation(s)
- Marie Kobylarski
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | - Louis Monsigny
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | - Pierre Thuéry
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | | | - Thibault Cantat
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
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17
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Planas F, Costantini M, Montesinos-Magraner M, Himo F, Mendoza A. Combined Experimental and Computational Study of Ruthenium N-Hydroxyphthalimidoyl Carbenes in Alkene Cyclopropanation Reactions. ACS Catal 2021; 11:10950-10963. [PMID: 34504736 PMCID: PMC8419840 DOI: 10.1021/acscatal.1c02540] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 08/05/2021] [Indexed: 01/14/2023]
Abstract
A combined experimental-computational approach has been used to study the cyclopropanation reaction of N-hydroxyphthalimide diazoacetate (NHPI-DA) with various olefins, catalyzed by a ruthenium-phenyloxazoline (Ru-Pheox) complex. Kinetic studies show that the better selectivity of the employed redox-active NHPI diazoacetate is a result of a much slower dimerization reaction compared to aliphatic diazoacetates. Density functional theory calculations reveal that several reactions can take place with similar energy barriers, namely, dimerization of the NHPI diazoacetate, cyclopropanation (inner-sphere and outer-sphere), and a previously unrecognized migratory insertion of the carbene into the phenyloxazoline ligand. The calculations show that the migratory insertion reaction yields an unconsidered ruthenium complex that is catalytically competent for both the dimerization and cyclopropanation, and its relevance is assessed experimentally. The stereoselectivity of the reaction is argued to stem from an intricate balance between the various mechanistic scenarios.
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Affiliation(s)
| | | | - Marc Montesinos-Magraner
- Department of Organic Chemistry,
Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Fahmi Himo
- Department of Organic Chemistry,
Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Abraham Mendoza
- Department of Organic Chemistry,
Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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18
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Jüstel PM, Rovó P, Mayr H, Ofial AR. Dynamics of the dimethyl sulfide exchange of (1,3‐diphenylallyl)dimethylsulfonium ions. J PHYS ORG CHEM 2021. [DOI: 10.1002/poc.4270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Patrick M. Jüstel
- Department Chemie Ludwig‐Maximilians‐Universität München Munich Germany
| | - Petra Rovó
- Department Chemie Ludwig‐Maximilians‐Universität München Munich Germany
| | - Herbert Mayr
- Department Chemie Ludwig‐Maximilians‐Universität München Munich Germany
| | - Armin R. Ofial
- Department Chemie Ludwig‐Maximilians‐Universität München Munich Germany
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19
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Chang R, Cai S, Yang G, Yan X, Huang H. Asymmetric Aminomethylative Etherification of Conjugated Dienes with Aliphatic Alcohols Facilitated by Hydrogen Bonding. J Am Chem Soc 2021; 143:12467-12472. [PMID: 34355892 DOI: 10.1021/jacs.1c06144] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The asymmetric construction of allylic C-O bonds with primary or secondary aliphatic alcohols remains a substantial challenge in Pd-catalyzed allylation chemistry. Here, we report the development of an additive-free, palladium-catalyzed asymmetric aminomethylative etherification of conjugated dienes that enables the efficient, asymmetric O-allylation of primary and secondary aliphatic alcohols as well as water. Mechanism studies revealed that the hydrogen-bonding interaction between the alcohol and the in situ introduced aminomethyl moiety is critical to facilitate the nucleophilic addition of the alcohol to the π-allylpalladium species, which opened up the possibility of using aliphatic alcohols and water as nucleophilic substrates. This reaction tolerates a broad range of functional groups and shows remarkable regioselectivities and uniformly high enantioselectivities, which provides a direct and rapid approach to optically pure allylic 1,3-amino ethers and 1,3-amino alcohols from simple starting materials.
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Affiliation(s)
- Rui Chang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, Center for Excellence in Molecular Synthesis of CAS, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Shoule Cai
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, Center for Excellence in Molecular Synthesis of CAS, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Guoqing Yang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, Center for Excellence in Molecular Synthesis of CAS, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Xuyang Yan
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, Center for Excellence in Molecular Synthesis of CAS, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Hanmin Huang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, Center for Excellence in Molecular Synthesis of CAS, University of Science and Technology of China, Hefei, 230026, People's Republic of China.,State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, People's Republic of China
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20
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Maji B, Duan XH, Jüstel PM, Byrne PA, Ofial AR, Mayr H. Nucleophilicities and Nucleofugalities of Thio- and Selenoethers. Chemistry 2021; 27:11367-11376. [PMID: 34002899 PMCID: PMC8456842 DOI: 10.1002/chem.202100977] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Indexed: 12/19/2022]
Abstract
Rate constants for the reactions of dialkyl chalcogenides with laser flash photolytically generated benzhydrylium ions have been measured photometrically to integrate them into the comprehensive benzhydrylium‐based nucleophilicity scale. Combining these rate constants with the previously reported equilibrium constants for the same reactions provided the corresponding Marcus intrinsic barriers and made it possible to quantify the leaving group abilities (nucleofugalities) of dialkyl sulfides and dimethyl selenide. Due to the low intrinsic barriers, dialkyl chalcogenides are fairly strong nucleophiles (comparable to pyridine and N‐methylimidazole) as well as good nucleofuges; this makes them useful group‐transfer reagents.
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Affiliation(s)
- Biplab Maji
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, München, Germany.,Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India
| | - Xin-Hua Duan
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, München, Germany.,Department of Chemistry, School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, No. 28, Xianning West Road, Xi'an, 710049, P. R. China
| | - Patrick M Jüstel
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, München, Germany
| | - Peter A Byrne
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, München, Germany.,School of Chemistry, University College Cork, College Road, Cork, Ireland
| | - Armin R Ofial
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, München, Germany
| | - Herbert Mayr
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, München, Germany
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21
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Rammah M, Mahdhaoui F, Gabsi W, Boubaker T. Quantification of the Electrophilic Reactivities of Benzotriazoles and Structure‐Reactivity Relationships. ChemistrySelect 2021. [DOI: 10.1002/slct.202100568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Mehdi Rammah
- Laboratoire C.H.P.N.R Faculté des Sciences de Monastir Université de Monastir Avenue de l'Environnement 5019 Monastir Tunisia
| | - Faouzi Mahdhaoui
- Laboratoire C.H.P.N.R Faculté des Sciences de Monastir Université de Monastir Avenue de l'Environnement 5019 Monastir Tunisia
| | - Wahiba Gabsi
- Laboratoire C.H.P.N.R Faculté des Sciences de Monastir Université de Monastir Avenue de l'Environnement 5019 Monastir Tunisia
| | - Taoufik Boubaker
- Laboratoire C.H.P.N.R Faculté des Sciences de Monastir Université de Monastir Avenue de l'Environnement 5019 Monastir Tunisia
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22
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Grundy ME, Yuan K, Nichol GS, Ingleson MJ. Zinc catalysed electrophilic C-H borylation of heteroarenes. Chem Sci 2021; 12:8190-8198. [PMID: 34194709 PMCID: PMC8208323 DOI: 10.1039/d1sc01883c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 05/12/2021] [Indexed: 01/20/2023] Open
Abstract
Cationic zinc Lewis acids catalyse the C-H borylation of heteroarenes using pinacol borane (HBPin) or catechol borane (HBCat). An electrophile derived from [IDippZnEt][B(C6F5)4] (IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) combined with N,N-dimethyl-p-toluidine (DMT) proved the most active in terms of C-H borylation scope and yield. Using this combination weakly activated heteroarenes, such as thiophene, were amenable to catalytic C-H borylation using HBCat. Competition reactions show these IDipp-zinc cations are highly oxophilic but less hydridophilic (relative to B(C6F5)3), and that borylation proceeds via activation of the hydroborane (and not the heteroarene) by a zinc electrophile. Based on DFT calculations this activation is proposed to proceed by coordination of a hydroborane oxygen to the zinc centre to generate a boron electrophile that effects C-H borylation. Thus, Lewis acid binding to oxygen sites of hydroboranes represents an under-developed route to access reactive borenium-type electrophiles for C-H borylation.
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Affiliation(s)
- Matthew E Grundy
- EaStCHEM School of Chemistry, University of Edinburgh Edinburgh EH9 3FJ UK
| | - Kang Yuan
- EaStCHEM School of Chemistry, University of Edinburgh Edinburgh EH9 3FJ UK
| | - Gary S Nichol
- EaStCHEM School of Chemistry, University of Edinburgh Edinburgh EH9 3FJ UK
| | - Michael J Ingleson
- EaStCHEM School of Chemistry, University of Edinburgh Edinburgh EH9 3FJ UK
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23
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Alexander JR, Kevorkian PV, Topczewski JJ. Silver Mediated Banert Cascade with Carbon Nucleophiles. Org Lett 2021; 23:3227-3230. [PMID: 33797930 DOI: 10.1021/acs.orglett.1c01032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Banert cascade of propargylic azides can be promoted by simple silver salts, and the triazafulvene intermediate can be intercepted by carbon nucleophiles. Various indoles (>25 examples, up to 92% yield) and electron-rich heterocycles were effective. The Mayr nucleophilicity parameter (N) was found to correlate to the reaction efficiency, which enabled the formation of Csp3-Csp2 and Csp3-Csp3 bonds under otherwise identical conditions from structurally dissimilar nucleophiles.
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Affiliation(s)
- Juliana R Alexander
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Paul V Kevorkian
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Joseph J Topczewski
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
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24
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Kadish D, Mood AD, Tavakoli M, Gutman ES, Baldi P, Van Vranken DL. Methyl Cation Affinities of Canonical Organic Functional Groups. J Org Chem 2021; 86:3721-3729. [PMID: 33596071 DOI: 10.1021/acs.joc.0c02327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Methyl cation affinities are calculated for the canonical nucleophilic functional groups in organic chemistry. These methyl cation affinities, calculated with a solvation model (MCA*), give an emprical correlation with the NsN term from the Mayr equation under aprotic conditions when they are scaled to the Mayr reference cation (4-MeOC6H4)2CH+ (Mayr E = 0). Highly reactive anionic nucleophiles were found to give a separate correlation, while some ylides and phosphorus compounds were determined to give a poor correlation. MCA*s are estimated for a broad range of simple molecules representing the canonical functional groups in organic chemistry. On the basis of a linear correlation, we estimate the range of nucleophilicities of organic functional groups, ranging from a C-C bond to a hypothetical tert-butyl carbanion, toward the reference electrophile to be about 50 orders of magnitude.
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Affiliation(s)
- Dora Kadish
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Aaron D Mood
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Mohammadamin Tavakoli
- Department of Computer Science, University of California, Irvine, California 92697, United States
| | - Eugene S Gutman
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Pierre Baldi
- Department of Computer Science, University of California, Irvine, California 92697, United States
| | - David L Van Vranken
- Department of Chemistry, University of California, Irvine, California 92697, United States
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25
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Orlandi M, Escudero-Casao M, Licini G. Nucleophilicity Prediction via Multivariate Linear Regression Analysis. J Org Chem 2021; 86:3555-3564. [PMID: 33534569 PMCID: PMC7901016 DOI: 10.1021/acs.joc.0c02952] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
The concept of nucleophilicity is
at the basis of most transformations
in chemistry. Understanding and predicting the relative reactivity
of different nucleophiles is therefore of paramount importance. Mayr’s
nucleophilicity scale likely represents the most complete collection
of reactivity data, which currently includes over 1200 nucleophiles.
Several attempts have been made to theoretically predict Mayr’s
nucleophilicity parameters N based on calculation
of molecular properties, but a general model accounting for different
classes of nucleophiles could not be obtained so far. We herein show
that multivariate linear regression analysis is a suitable tool for
obtaining a simple model predicting N for virtually
any class of nucleophiles in different solvents for a set of 341 data
points. The key descriptors of the model were found to account for
the proton affinity, solvation energies, and sterics.
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Affiliation(s)
- Manuel Orlandi
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.,CIRCC-Consorzio Interuniversitario per le Reattività Chimiche e la Catalisi, Padova Unit, via Marzolo 1, 35131 Padova, Italy
| | - Margarita Escudero-Casao
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.,CIRCC-Consorzio Interuniversitario per le Reattività Chimiche e la Catalisi, Padova Unit, via Marzolo 1, 35131 Padova, Italy
| | - Giulia Licini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.,CIRCC-Consorzio Interuniversitario per le Reattività Chimiche e la Catalisi, Padova Unit, via Marzolo 1, 35131 Padova, Italy
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26
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Fang J, Howard EM, Brewer M. A Conjugate Addition Approach to Diazo-Containing Scaffolds with β Quaternary Centers. Angew Chem Int Ed Engl 2020; 59:12827-12831. [PMID: 32365265 PMCID: PMC11157584 DOI: 10.1002/anie.202004557] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/28/2020] [Indexed: 01/25/2023]
Abstract
Structurally complex diazo-containing scaffolds are formed by conjugate addition to vinyl diazonium salts. The electrophile, a little studied α-diazonium-α,β-unsaturated carbonyl compound, is formed at low temperature under mild conditions by treating β-hydroxy-α-diazo carbonyls with Sc(OTf)3 . Conjugate addition occurs selectively at the 3-position of indole to give α-diazo-β-indole carbonyls, and enoxy silanes react to give 2-diazo-1,4-dicarbonyl products. These reactions result in the formation of tertiary and quaternary centers, and give products that would be otherwise difficult to form. Importantly, the diazo functional group is retained within the molecule for future manipulation. Treating an α-diazo ester indole addition product with Rh2 (OAc)4 caused a rearrangement to occur to give a 2-(1H-indol-3-yl)-2-enoate. In the case of diazo ketone compounds, this shift occurred spontaneously on prolonged exposure to the Lewis acidic reaction conditions.
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Affiliation(s)
- Jian Fang
- Department of Chemistry, University of Vermont, Innovation Hall, 82 University Place, Burlington, VT, 05495, USA
| | - Evan M Howard
- Department of Chemistry, University of Vermont, Innovation Hall, 82 University Place, Burlington, VT, 05495, USA
| | - Matthias Brewer
- Department of Chemistry, University of Vermont, Innovation Hall, 82 University Place, Burlington, VT, 05495, USA
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27
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Fang J, Howard EM, Brewer M. A Conjugate Addition Approach to Diazo‐Containing Scaffolds with β Quaternary Centers. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004557] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Jian Fang
- Department of Chemistry University of Vermont Innovation Hall, 82 University Place Burlington VT 05495 USA
| | - Evan M. Howard
- Department of Chemistry University of Vermont Innovation Hall, 82 University Place Burlington VT 05495 USA
| | - Matthias Brewer
- Department of Chemistry University of Vermont Innovation Hall, 82 University Place Burlington VT 05495 USA
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28
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Mood A, Tavakoli M, Gutman E, Kadish D, Baldi P, Van Vranken DL. Methyl Anion Affinities of the Canonical Organic Functional Groups. J Org Chem 2020; 85:4096-4102. [PMID: 31995384 DOI: 10.1021/acs.joc.9b03187] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Calculated methyl anion affinities are known to correlate with experimentally determined Mayr E parameters for individual organic functional group classes but not between neutral and cationic organic electrophiles. We demonstrate that methyl anion affinities calculated with a solvation model (MAA*) give a linear correlation with Mayr E parameters for a broad range of functional groups. Methyl anion affinities (MAA*), plotted on the log scale of Mayr E, provide insights into the full range of electrophilicity of organic functional groups. On the Mayr E scale, the electrophilicity toward the methyl anion spans 180 orders of magnitude.
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Affiliation(s)
- Aaron Mood
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Mohammadamin Tavakoli
- Department of Computer Science, University of California Irvine, Irvine, California 92697, United States
| | - Eugene Gutman
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Dora Kadish
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Pierre Baldi
- Department of Computer Science, University of California Irvine, Irvine, California 92697, United States
| | - David L Van Vranken
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
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29
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Bartolo ND, Read JA, Valentín EM, Woerpel KA. Reactions of Allylmagnesium Reagents with Carbonyl Compounds and Compounds with C═N Double Bonds: Their Diastereoselectivities Generally Cannot Be Analyzed Using the Felkin-Anh and Chelation-Control Models. Chem Rev 2020; 120:1513-1619. [PMID: 31904936 PMCID: PMC7018623 DOI: 10.1021/acs.chemrev.9b00414] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This review describes the additions of allylmagnesium reagents to carbonyl compounds and to imines, focusing on the differences in reactivity between allylmagnesium halides and other Grignard reagents. In many cases, allylmagnesium reagents either react with low stereoselectivity when other Grignard reagents react with high selectivity, or allylmagnesium reagents react with the opposite stereoselectivity. This review collects hundreds of examples, discusses the origins of stereoselectivities or the lack of stereoselectivity, and evaluates why selectivity may not occur and when it will likely occur.
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Affiliation(s)
- Nicole D. Bartolo
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
| | - Jacquelyne A. Read
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
- Department of Chemistry, University of Utah, 315 South 1400
East, Salt Lake City, UT 84112, USA
| | - Elizabeth M. Valentín
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
- Department of Chemistry, Susquehanna University, 514
University Avenue, Selinsgrove, PA 17870, USA
| | - K. A. Woerpel
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
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30
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Ghorai S, Lin Y, Xia Y, Wink DJ, Lee D. Silver-Catalyzed Selective Multicomponent Coupling Reactions of Arynes with Nitriles and Isonitriles. Org Lett 2019; 22:642-647. [PMID: 31891273 DOI: 10.1021/acs.orglett.9b04416] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sourav Ghorai
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Yongjia Lin
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang Province 325035, P. R. China
| | - Yuanzhi Xia
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang Province 325035, P. R. China
| | - Donald J. Wink
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Daesung Lee
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
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31
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Rahrt R, Auth T, Demireva M, Armentrout PB, Koszinowski K. Benzhydrylpyridinium Ions: A New Class of Thermometer Ions for the Characterization of Electrospray-Ionization Mass Spectrometers. Anal Chem 2019; 91:11703-11711. [DOI: 10.1021/acs.analchem.9b02257] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Rene Rahrt
- Institut für Organische und Biomolekulare Chemie, Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Thomas Auth
- Institut für Organische und Biomolekulare Chemie, Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Maria Demireva
- Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112, United States
| | - P. B. Armentrout
- Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112, United States
| | - Konrad Koszinowski
- Institut für Organische und Biomolekulare Chemie, Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
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32
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Affiliation(s)
- Lucas Schreyer
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Deutschland
| | - Roberta Properzi
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Deutschland
| | - Benjamin List
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Deutschland
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33
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Abstract
High acidity and structural confinement are pivotal elements in asymmetric acid catalysis. The recently introduced imidodiphosphorimidate (IDPi) Brønsted acids have met with remarkable success in combining those features, acting as powerful Brønsted acid catalysts and "silylium" Lewis acid precatalysts in numerous thus far inaccessible transformations. Substrates as challenging to activate as simple olefins were readily transformed, ketones were employed as acceptors in aldolizations allowing sub-ppm level catalysis, whereas enolates of the smallest donor aldehyde, acetaldehyde, did not polymerize but selectively added a single time to a variety of acceptor aldehydes.
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Affiliation(s)
- Lucas Schreyer
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Roberta Properzi
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Benjamin List
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
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34
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Bendelsmith AJ, Kim SC, Wasa M, Roche SP, Jacobsen EN. Enantioselective Synthesis of α-Allyl Amino Esters via Hydrogen-Bond-Donor Catalysis. J Am Chem Soc 2019; 141:11414-11419. [PMID: 31280564 PMCID: PMC7293823 DOI: 10.1021/jacs.9b05556] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We report a chiral-squaramide-catalyzed enantio- and diastereoselective synthesis of α-allyl amino esters. The optimized protocol provides access to N-carbamoyl-protected amino esters via nucleophilic allylation of readily accessible α-chloro glycinates. A variety of useful α-allyl amino esters were prepared, including crotylated products bearing vicinal stereocenters that are inaccessible through enolate alkylation, with high enantioselectivity (up to 97% ee) and diastereoselectivity (>10:1). The reactions display first-order kinetic dependence on both the α-chloro glycinate and the nucleophile, consistent with rate-limiting C-C bond formation. Computational analysis of the uncatalyzed reaction predicts an energetically inaccessible iminium intermediate, and a lower energy concerted SN2 mechanism.
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Affiliation(s)
- Andrew J Bendelsmith
- Department of Chemistry & Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Seohyun Chris Kim
- Department of Chemistry & Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Masayuki Wasa
- Department of Chemistry & Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Stéphane P Roche
- Department of Chemistry & Biochemistry , Florida Atlantic University , Boca Raton , Florida 33431 , United States
| | - Eric N Jacobsen
- Department of Chemistry & Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
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35
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Kim Y, Choi YS, Hong SK, Park YS. Friedel-Crafts alkylation with α-bromoarylacetates for the preparation of enantioenriched 2,2-diarylethanols. Org Biomol Chem 2019; 17:4554-4563. [PMID: 30994667 DOI: 10.1039/c9ob00706g] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Highly enantioenriched 2,2-diarylethanols can be efficiently synthesized through the Friedel-Crafts alkylation of (hetero)arenes with configurationally labile α-bromoarylacetates. The substitution of highly diastereoenriched α-bromoarylacetates occurs in the presence of AgOTf, and the subsequent reduction affords diverse 2,2-diarylethanols with high yields and enantioselectivities up to 99 : 1 er. In addition, the application of this asymmetric synthetic methodology to the preparation of highly enantioenriched dihydrobenzofuran and indoline derivatives is demonstrated.
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Affiliation(s)
- Yongtae Kim
- Department of Chemistry, Konkuk University, Seoul 05029, Republic of Korea.
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36
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Marijan M, Jurić S, Mihalić Z, Kronja O. Impact of the α‐Ferrocenyl Group on the Solvolytic Reactivity – Electrofugality – of Ferrocenylphenylmethyl Cations. European J Org Chem 2019. [DOI: 10.1002/ejoc.201801133] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marijan Marijan
- Faculty of Pharmacy and Biochemistry University of Zagreb Ante Kovačića 1 10000 Zagreb Croatia
| | - Sandra Jurić
- Faculty of Pharmacy and Biochemistry University of Zagreb Ante Kovačića 1 10000 Zagreb Croatia
| | - Zlatko Mihalić
- Faculty of Sciences Department of Chemistry University of Zagreb Horvatovac 105a 10000 Zagreb Croatia
| | - Olga Kronja
- Faculty of Pharmacy and Biochemistry University of Zagreb Ante Kovačića 1 10000 Zagreb Croatia
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37
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van der Vorm S, Hansen T, van Hengst JMA, Overkleeft HS, van der Marel GA, Codée JDC. Acceptor reactivity in glycosylation reactions. Chem Soc Rev 2019; 48:4688-4706. [DOI: 10.1039/c8cs00369f] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effect of the reactivity of the glycosyl acceptor on the outcome of glycosylation reactions is reviewed.
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Affiliation(s)
| | - Thomas Hansen
- Leiden Institute of Chemistry
- Leiden University
- 2333 CC Leiden
- The Netherlands
| | | | | | | | - Jeroen D. C. Codée
- Leiden Institute of Chemistry
- Leiden University
- 2333 CC Leiden
- The Netherlands
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38
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Voll CCA, Swager TM. Extended π-Conjugated Structures via Dehydrative C-C Coupling. J Am Chem Soc 2018; 140:17962-17967. [PMID: 30550269 DOI: 10.1021/jacs.8b09337] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We describe a methodology for the synthesis of extended aromatic structures through dehydrative C-C coupling from readily accessible diols. Treatment of the diols with a Brønsted acid ( para-toluenesulfonic acid) induces the nucleophilic addition of an arene or heteroarene, yielding fully aromatic products in high to quantitative yields with thiophenes, furan, indole, and N, N-dimethylaniline as coupling partners. The C-C coupling reactions proceed under mild, open flask conditions and offer high atom economy, while providing an attractive alternative approach to metal-catalyzed cross-coupling.
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Affiliation(s)
- Constantin-Christian A Voll
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Timothy M Swager
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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39
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Pearce KG, Borys AM, Clark ER, Shepherd HJ. Exploring the Reactivity of Donor-Stabilized Phosphenium Cations: Lewis Acid-Catalyzed Reduction of Chlorophosphanes by Silanes. Inorg Chem 2018; 57:11530-11536. [DOI: 10.1021/acs.inorgchem.8b01578] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Kyle G. Pearce
- School of Physical Sciences, University of Kent, Ingram Building, Canterbury, Kent CT2 7NH, United Kingdom of Great Britain and Northern Ireland
| | - Andryj M. Borys
- School of Physical Sciences, University of Kent, Ingram Building, Canterbury, Kent CT2 7NH, United Kingdom of Great Britain and Northern Ireland
| | - Ewan R. Clark
- School of Physical Sciences, University of Kent, Ingram Building, Canterbury, Kent CT2 7NH, United Kingdom of Great Britain and Northern Ireland
| | - Helena J. Shepherd
- School of Physical Sciences, University of Kent, Ingram Building, Canterbury, Kent CT2 7NH, United Kingdom of Great Britain and Northern Ireland
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40
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Mayer RJ, Hampel N, Mayer P, Ofial AR, Mayr H. Synthesis, Structure, and Properties of Amino-Substituted Benzhydrylium Ions - A Link between Ordinary Carbocations and Neutral Electrophiles. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800835] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Robert J. Mayer
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstraße 5-13 81377 München Germany
| | - Nathalie Hampel
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstraße 5-13 81377 München Germany
| | - Peter Mayer
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstraße 5-13 81377 München Germany
| | - Armin R. Ofial
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstraße 5-13 81377 München Germany
| | - Herbert Mayr
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstraße 5-13 81377 München Germany
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41
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Timofeeva DS, Ofial AR, Mayr H. Kinetics of Electrophilic Fluorinations of Enamines and Carbanions: Comparison of the Fluorinating Power of N–F Reagents. J Am Chem Soc 2018; 140:11474-11486. [DOI: 10.1021/jacs.8b07147] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Daria S. Timofeeva
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München, Germany
| | - Armin R. Ofial
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München, Germany
| | - Herbert Mayr
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 München, Germany
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42
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Gabsi W, Essalah K, Goumont R, Tangour B, Boubaker T. The ambident electrophilic behavior of 5-nitro-3-X-thiophenes in σ-complexation processes. INT J CHEM KINET 2018. [DOI: 10.1002/kin.21190] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Wahiba Gabsi
- Laboratoire C.H.P.N.R, Faculté des Sciences de Monastir; Université de Monastir; Monastir Tunisia
| | - Khalid Essalah
- Unité de Recherche en Sciences Fondamentales et Didactique; Université de Tunis EL Manar; El Manar II Tunisia
| | - Régis Goumont
- Institut Lavoisier de Versailles, UMR 8180; Université de Versailles; Versailles Cedex France
| | - Bahoueddine Tangour
- Unité de Recherche en Sciences Fondamentales et Didactique; Université de Tunis EL Manar; El Manar II Tunisia
| | - Taoufik Boubaker
- Laboratoire C.H.P.N.R, Faculté des Sciences de Monastir; Université de Monastir; Monastir Tunisia
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43
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Kumara MN, Nakahara T, Kobayashi S, Fujio M, Mishima M. Nucleophilicities of Alcohols and Water in Acetonitrile Based on Reactivities of Benzhydrylium Ions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2018. [DOI: 10.1246/bcsj.20170360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Manikyanahally N. Kumara
- Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Tesshu Nakahara
- Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Shinjiro Kobayashi
- Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Mizue Fujio
- Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Masaaki Mishima
- Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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44
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Wang F, Sun W, Wang Y, Jiang Y, Loh TP. Highly Site-Selective Metal-Free C–H Acyloxylation of Stable Enamines. Org Lett 2018; 20:1256-1260. [DOI: 10.1021/acs.orglett.8b00222] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Fei Wang
- Institute
of Advanced Synthesis, Institute of Advanced Materials, School of
Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation
Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Wangbing Sun
- Institute
of Advanced Synthesis, Institute of Advanced Materials, School of
Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation
Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Yixin Wang
- Institute
of Advanced Synthesis, Institute of Advanced Materials, School of
Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation
Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Yaojia Jiang
- Institute
of Advanced Synthesis, Institute of Advanced Materials, School of
Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation
Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Teck-Peng Loh
- Institute
of Advanced Synthesis, Institute of Advanced Materials, School of
Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation
Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, Singapore 637616, Singapore
- Department
of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
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45
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Li S, Liu B, Chen L, Li X, Cheng JP. N-Heterocyclic carbene promoted enantioselective desymmetrization reaction of diarylalkane-bisphenols. Org Chem Front 2018. [DOI: 10.1039/c7qo01083d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An enantioselective NHC-catalyzed desymmetrization reaction of diarylalkane-bisphenols with aldehydes was reported under the guidance of linear free energy relationships (LFERs).
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Affiliation(s)
- Shoulei Li
- State Key Laboratory of Elemento-Organic Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
- China
| | - Bin Liu
- State Key Laboratory of Elemento-Organic Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
- China
| | - Li Chen
- State Key Laboratory of Elemento-Organic Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
- China
| | - Xin Li
- State Key Laboratory of Elemento-Organic Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
- China
| | - Jin-Pei Cheng
- State Key Laboratory of Elemento-Organic Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering
- Nankai University
- Tianjin 300071
- China
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46
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Đorđević N, Ganguly R, Petković M, Vidović D. E–H (E = B, Si, C) Bond Activation by Tuning Structural and Electronic Properties of Phosphenium Cations. Inorg Chem 2017; 56:14671-14681. [DOI: 10.1021/acs.inorgchem.7b02579] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nemanja Đorđević
- SPMS-CBC, Nanyang Technological University, 21 Nanyang Link, Singapore 638737
| | - Rakesh Ganguly
- SPMS-CBC, Nanyang Technological University, 21 Nanyang Link, Singapore 638737
| | - Milena Petković
- Faculty
of Physical Chemistry, University of Belgrade, 11000 Belgrade, Republic of Serbia
| | - Dragoslav Vidović
- SPMS-CBC, Nanyang Technological University, 21 Nanyang Link, Singapore 638737
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47
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Azaiez K, Dhahri N, Boubaker T. Reactivity of Nitroalkyl Anions Addition to Substituted Benzylidenecyanoacetates: Electrophilicity Parameters and Free Energy Relationships. INT J CHEM KINET 2017. [DOI: 10.1002/kin.21132] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- K. Azaiez
- Laboratoire C.H.P.N.R; Faculté des Sciences de Monastir; Université de Monastir; 5019 Monastir Tunisie
| | - N. Dhahri
- Laboratoire C.H.P.N.R; Faculté des Sciences de Monastir; Université de Monastir; 5019 Monastir Tunisie
| | - T. Boubaker
- Laboratoire C.H.P.N.R; Faculté des Sciences de Monastir; Université de Monastir; 5019 Monastir Tunisie
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48
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Samanta SS, Roche SP. In Situ-Generated Glycinyl Chloroaminals for a One-Pot Synthesis of Non-proteinogenic α-Amino Esters. J Org Chem 2017; 82:8514-8526. [PMID: 28737944 DOI: 10.1021/acs.joc.7b01274] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
An acetyl chloride-mediated cascade transformation involving a primary carbamate, ethyl glyoxylate, and various types of nucleophiles is reported for the synthesis of orthogonally protected α-amino esters. These reactions proceeded rapidly to afford the pivotal α-chloroglycine intermediate in excellent yields, which can be directly functionalized in situ with various types of nucleophiles. A mild and unique AcOH(cat.)/AcCl system was found to promote an autocatalytic-like condensation and facilitate the multicomponent assembly of non-proteinogenic α-amino esters. To better understand this one-pot transformation and the orchestration of the components' condensations, the investigation of a broader scope of nucleophiles and some kinetic studies are presented. Our findings suggest that the halogenation step toward the formation of α-chloroglycine is the rate-determining step likely proceeding through the formation of N-carbamoyl iminium. Also, the initial kinetic profiling for the nucleophilic substitution supports an SN1-like (SN2C+) mechanism in which nucleophiles add to the iminium-chloride tight ionic pair. These results lead ultimately to the design of a new protocol in which an achiral hydrogen bond donor thiourea catalyst was utilized to enhance the reaction scope and enable silylated nucleophiles to be efficiently exploited to synthesize novel non-proteinogenic α-amino esters.
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Affiliation(s)
- Shyam S Samanta
- Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States
| | - Stéphane P Roche
- Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States
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49
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Mayr H, Ofial AR. Philicity, fugality, and equilibrium constants: when do rate-equilibrium relationships break down? PURE APPL CHEM 2017. [DOI: 10.1515/pac-2017-0107] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractLinear free energy relationships, in particular relationships between rate and equilibrium constants, are the basis for our rationalization of organic reactivity. Whereas relationships between the kinetic terms nucleophilicity and nucleofugality and the thermodynamic term basicity have been in the focus of interest for many decades, much less attention has been paid to the relationships between electrophilicity, electrofugality, and Lewis acidity. By using p- and m-substituted benzhydrylium ions (Aryl2CH+) as reference electrophiles, reference electrofuges, and reference Lewis acids of widely varying electron demand and constant steric surroundings of the reaction center, we have developed comprehensive reactivity scales which can be employed for classifying polar organic reactivity and for rationally designing synthetic transformations. It is a general rule that structural variations in electron-surplus species, which increase basicities, also increase nucleophilicities and decrease nucleofugalities, and that structural variations in electron-deficient species, which increase Lewis acidities also increase electrophilicities and decrease electrofugalities. Deviations from this behavior are analyzed, and it is shown that variations in intrinsic barriers are responsible for the counterintuitive observations that structural variation in one of the reactants alters the rates of forward and backward reactions in the same direction. A spectacular example of this phenomenon is found in vinyl cation chemistry: Vinyl cations are not only generated several orders of magnitude more slowly in SN1 reactions than benzhydrylium ions of the same Lewis acidity, but also react much more slowly with nucleophiles.
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Affiliation(s)
- Herbert Mayr
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany
| | - Armin R. Ofial
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany
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50
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Salah SB, Boubaker T, Goumont R. Reactions of N1-Methyl-4-nitro-2,1,3-benzoselenadiazolium Tetrafluoroborate with Aliphatic and Cyclic Amines in Acetonitrile: Kinetic and Structure-Reactivity Correlations. INT J CHEM KINET 2017. [DOI: 10.1002/kin.21096] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- S. Ben Salah
- Laboratoire C.H.P.N.R; Faculté des Sciences de Monastir; Université de Monastir; Avenue de l’Environnement 5019 Monastir Tunisie
| | - T. Boubaker
- Laboratoire C.H.P.N.R; Faculté des Sciences de Monastir; Université de Monastir; Avenue de l’Environnement 5019 Monastir Tunisie
| | - R. Goumont
- Institut Lavoisier de Versailles; UMR 8180, Université de Versailles, 45; Avenue des Etats-Unis 78035 Versailles Cedex France
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