1
|
Kong L, Gan XC, van der Puyl Lovett VA, Shenvi RA. Alkene Hydrobenzylation by a Single Catalyst That Mediates Iterative Outer-Sphere Steps. J Am Chem Soc 2024; 146:2351-2357. [PMID: 38232310 DOI: 10.1021/jacs.3c13398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Cross-coupling catalysts typically react and unite functionally distinct partners via sequential inner-sphere elementary steps: coordination, migratory insertion, reductive elimination, etc. Here, we report a single catalyst that cross-couples styrenes and benzyl bromides via iterative outer-sphere steps: metal-ligand-carbon interactions. Each partner forms a stabilized radical intermediate, yet heterocoupled products predominate. The system is redox-neutral and, thus, avoids exogenous oxidants, resulting in simple and scalable conditions. Numerous variations of alkene hydrobenzylation are made possible, including access to the privileged heterodibenzyl (1,2-diarylethane) motif and challenging quaternary carbon variants.
Collapse
Affiliation(s)
- Lingran Kong
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Xu-Cheng Gan
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Vincent A van der Puyl Lovett
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
- Graduate School of Chemical and Biological Sciences, Scripps Research, La Jolla, California 92037, United States
| | - Ryan A Shenvi
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
- Graduate School of Chemical and Biological Sciences, Scripps Research, La Jolla, California 92037, United States
| |
Collapse
|
2
|
Shu C, Yang Z, Rajca A. From Stable Radicals to Thermally Robust High-Spin Diradicals and Triradicals. Chem Rev 2023; 123:11954-12003. [PMID: 37831948 DOI: 10.1021/acs.chemrev.3c00406] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2023]
Abstract
Stable radicals and thermally robust high-spin di- and triradicals have emerged as important organic materials due to their promising applications in diverse fields. New fundamental properties, such as SOMO/HOMO inversion of orbital energies, are explored for the design of new stable radicals, including highly luminescent ones with good photostability. A relation with the singlet-triplet energy gap in the corresponding diradicals is proposed. Thermally robust high-spin di- and triradicals, with energy gaps that are comparable to or greater than a thermal energy at room temperature, are more challenging to synthesize but more rewarding. We summarize a number of high-spin di- and triradicals, based on nitronyl nitroxides that provide a relation between the experimental pairwise exchange coupling constant J/k in the high-spin species vs experimental hyperfine coupling constants in the corresponding monoradicals. This relation allows us to identify outliers, which may correspond to radicals where J/k is not measured with sufficient accuracy. Double helical high-spin diradicals, in which spin density is delocalized over the chiral π-system, have been barely explored, with the sole example of such high-spin diradical possessing alternant π-system with Kekulé resonance form. Finally, we discuss a high-spin diradical with electrical conductivity and derivatives of triangulene diradicals.
Collapse
Affiliation(s)
- Chan Shu
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - Zhimin Yang
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - Andrzej Rajca
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| |
Collapse
|
3
|
Heuer A, Coste SC, Singh G, Mercado BQ, Mayer JM. A Guide to Tris(4-Substituted)-triphenylmethyl Radicals. J Org Chem 2023; 88:9893-9901. [PMID: 37403939 PMCID: PMC10367072 DOI: 10.1021/acs.joc.3c00658] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Indexed: 07/06/2023]
Abstract
Triphenylmethyl (trityl, Ph3C•) radicals have been considered the prototypical carbon-centered radical since their discovery in 1900. Tris(4-substituted)-trityls [(4-R-Ph)3C•] have since been used in many ways due to their stability, persistence, and spectroscopic activity. Despite their widespread use, existing synthetic routes toward tris(4-substituted)-trityl radicals are not reproducible and often lead to impure materials. We report here robust syntheses of six electronically varied (4-RPh)3C•, where R = NMe2, OCH3, tBu, Ph, Cl, and CF3. The characterization reported for the radicals and related compounds includes five X-ray crystal structures, electrochemical potentials, and optical spectra. Each radical is best accessed using a stepwise approach from the trityl halide, (RPh)3CCl or (RPh)3CBr, by controllably removing the halide with subsequent 1e- reduction of the trityl cation, (RPh)3C+. These syntheses afford consistently crystalline trityl radicals of high purity for further studies.
Collapse
Affiliation(s)
| | | | - Gurjot Singh
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Brandon Q. Mercado
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - James M. Mayer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| |
Collapse
|
4
|
Lee H, Ahn JM, Oyala PH, Citek C, Yin H, Fu GC, Peters JC. Investigation of the C-N Bond-Forming Step in a Photoinduced, Copper-Catalyzed Enantioconvergent N-Alkylation: Characterization and Application of a Stabilized Organic Radical as a Mechanistic Probe. J Am Chem Soc 2022; 144:4114-4123. [PMID: 35167268 PMCID: PMC9269863 DOI: 10.1021/jacs.1c13151] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Whereas photoinduced, copper-catalyzed couplings of nitrogen nucleophiles with alkyl electrophiles have recently been shown to provide an attractive approach to achieving a variety of enantioselective C-N bond constructions, mechanistic studies of these transformations have lagged the advances in reaction development. Herein we provide mechanistic insight into a previously reported photoinduced, copper-catalyzed enantioconvergent C-N coupling of a carbazole nucleophile with a racemic tertiary α-haloamide electrophile. Building on the isolation of a copper(II) model complex whose EPR parameters serve as a guide, we independently synthesize two key intermediates in the proposed catalytic cycle, a copper(II) metalloradical (L*CuII(carb')2) (L* = a monodentate chiral phosphine ligand; carb' = a carbazolide ligand), as well as a tertiary α-amide organic radical (R·); the generation and characterization of R· was guided by DFT calculations, which suggested that it would be stable to homocoupling. Continuous-wave (CW) and pulse EPR studies, along with corresponding DFT calculations, are among the techniques used to characterize these reactive radicals. We establish that these two radicals do indeed combine to furnish the C-N coupling product in good yield and with significant enantiomeric excess (77% yield, 55% ee), thereby supporting the chemical competence of these proposed intermediates. DFT calculations are consistent with R· initially binding to copper(II) via a dative interaction from the closed-shell carbonyl oxygen atom of the radical, which positions the α-carbon for direct reaction with the copper(II)-bound carbazole N atom, to generate the C-N bond with enantioselectivity, without the formation of an alkylcopper(III) intermediate.
Collapse
Affiliation(s)
- Heejun Lee
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Jun Myun Ahn
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Paul H Oyala
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Cooper Citek
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Haolin Yin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Gregory C Fu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Jonas C Peters
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| |
Collapse
|
5
|
Rösel S, Schreiner PR. Computational Chemistry as a Conceptual Game Changer: Understanding the Role of London Dispersion in Hexaphenylethane Derivatives (Gomberg Systems). Isr J Chem 2022. [DOI: 10.1002/ijch.202200002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Sören Rösel
- Institute of Organic Chemistry Justus Liebig University Heinrich-Buff-Ring 17, Twitter: @prsgroupjlu 35392 Giessen Germany
| | - Peter R. Schreiner
- Institute of Organic Chemistry Justus Liebig University Heinrich-Buff-Ring 17, Twitter: @prsgroupjlu 35392 Giessen Germany
| |
Collapse
|
6
|
Casper LA, Linseis M, Demeshko S, Azarkh M, Drescher M, Winter RF. Tailoring Valence Tautomerism by Using Redox Potentials: Studies on Ferrocene-Based Triarylmethylium Dyes with Electron-Poor Fluorenylium and Thioxanthylium Acceptors. Chemistry 2021; 27:10854-10868. [PMID: 33901313 PMCID: PMC8361958 DOI: 10.1002/chem.202101032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Indexed: 01/31/2023]
Abstract
Three new electrochromic ferrocenyl triarylmethylium dyes with fluorenylium (1 a+ , 1 b+ ) or thioxanthylium (1 c+ ) residues were selected in order to keep the intrinsic differences of redox potentials for ferrocene oxidation and triarylmethylium reduction small and to trigger valence tautomerism (VT). UV/Vis/NIR and quantitative EPR spectroscopy identified paramagnetic diradical isomers 1 a..+ -1 c..+ alongside diamagnetic forms 1 a+ -1 c+ , which renders these complexes magnetochemical switches. The diradical forms 1 a..+ -1 c..+ as well as the one-electron-reduced triarylmethyl forms of the complexes were found to dimerize in solution. For radical 1 a. , dimerization occurs on the timescale of cyclic voltammetry; this allowed us to determine the kinetics and equilibrium constant for this process by digital simulation. Mößbauer spectroscopy indicated that 1 a+ and 1 b+ retain VT even in the solid state. UV/Vis/NIR spectro-electrochemistry revealed the poly-electrochromic behaviour of these complexes by establishing the distinctly different electronic absorption profiles of the corresponding oxidized and reduced forms.
Collapse
Affiliation(s)
- Larissa A Casper
- Fachbereich Chemie, Universität Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Michael Linseis
- Fachbereich Chemie, Universität Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Serhiy Demeshko
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstraße 4, 37077, Göttingen, Germany
| | - Mykhailo Azarkh
- Fachbereich Chemie, Universität Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Malte Drescher
- Fachbereich Chemie, Universität Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Rainer F Winter
- Fachbereich Chemie, Universität Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| |
Collapse
|
7
|
Cummins DC, Alvarado JG, Zaragoza JPT, Effendy Mubarak MQ, Lin YT, de Visser SP, Goldberg DP. Hydroxyl Transfer to Carbon Radicals by Mn(OH) vs Fe(OH) Corrole Complexes. Inorg Chem 2020; 59:16053-16064. [PMID: 33047596 DOI: 10.1021/acs.inorgchem.0c02640] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The transfer of •OH from metal-hydroxo species to carbon radicals (R•) to give hydroxylated products (ROH) is a fundamental process in metal-mediated heme and nonheme C-H bond oxidations. This step, often referred to as the hydroxyl "rebound" step, is typically very fast, making direct study of this process challenging if not impossible. In this report, we describe the reactions of the synthetic models M(OH)(ttppc) (M = Fe (1), Mn (3); ttppc = 5,10,15-tris(2,4,6-triphenyl)phenyl corrolato3-) with a series of triphenylmethyl carbon radical (R•) derivatives ((4-X-C6H4)3C•; X = OMe, tBu, Ph, Cl, CN) to give the one-electron reduced MIII(ttppc) complexes and ROH products. Rate constants for 3 for the different radicals ranged from 11.4(1) to 58.4(2) M-1 s-1, as compared to those for 1, which fall between 0.74(2) and 357(4) M-1 s-1. Linear correlations for Hammett and Marcus plots for both Mn and Fe were observed, and the small magnitudes of the slopes for both correlations imply a concerted •OH transfer reaction for both metals. Eyring analyses of reactions for 1 and 3 with (4-X-C6H4)3C• (X = tBu, CN) also give good linear correlations, and a comparison of the resulting activation parameters highlight the importance of entropy in these •OH transfer reactions. Density functional theory calculations of the reaction profiles show a concerted process with one transition state for all radicals investigated and help to explain the electronic features of the OH rebound process.
Collapse
Affiliation(s)
- Daniel C Cummins
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Jessica G Alvarado
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Jan Paulo T Zaragoza
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Muhammad Qadri Effendy Mubarak
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Yen-Ting Lin
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Sam P de Visser
- Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| |
Collapse
|
8
|
Casper LA, Wursthorn L, Geppert M, Roser P, Linseis M, Drescher M, Winter RF. 4-Ferrocenylphenyl-Substituted Tritylium Dyes with Open and Interlinked C +Ar 2 Entities: Redox Behavior, Electrochromism, and a Quantitative Study of the Dimerization of Their Neutral Radicals. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00486] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Larissa A. Casper
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Lukas Wursthorn
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Marcel Geppert
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Patrick Roser
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Michael Linseis
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Malte Drescher
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Rainer F. Winter
- Department of Chemistry, Universität Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| |
Collapse
|
9
|
Mandal D, Sobottka S, Dolai R, Maiti A, Dhara D, Kalita P, Narayanan RS, Chandrasekhar V, Sarkar B, Jana A. Direct access to 2-aryl substituted pyrrolinium salts for carbon centre based radicals without pyrrolidine-2-ylidene alias cyclic(alkyl)(amino)carbene (CAAC) as a precursor. Chem Sci 2019; 10:4077-4081. [PMID: 31049189 PMCID: PMC6470959 DOI: 10.1039/c8sc05477k] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/27/2019] [Indexed: 12/20/2022] Open
Abstract
A new strategy to synthesise 2-substituted pyrrolinium salts.
The synthesis of organic radicals is challenging due to their inherent instability. In recent years, cyclic(alkyl)(amino)carbene (CAAC)-derived 2-substituted pyrrolinium salts have been used as synthons for the synthesis of isolable carbon-based radicals. Herein, we report a direct, easy and convenient method for the synthesis of 2-aryl substituted pyrrolinium salts without using CAAC as a precursor. These cations can be reduced to the corresponding radicals. The influence of the aryl substituent at the C-2 position on radical stabilization and dimerization has been investigated. Because of the large scope of our strategy (capability to modulate different substituents at all the C- and N-centres of the pyrrolinium salts), it has the merit to be an extremely effective and productive route for generating carbon-based radicals whose stability as well as reactivity can be varied.
Collapse
Affiliation(s)
- Debdeep Mandal
- Tata Institute of Fundamental Research Hyderabad , Gopanpally , Hyderabad-500107 , Telangana , India .
| | - Sebastian Sobottka
- Institut für Chemie und Biochemie, Anorganische Chemie , Freie Universität Berlin , Fabeckstraße 34-36 , 14195 , Berlin , Germany .
| | - Ramapada Dolai
- Tata Institute of Fundamental Research Hyderabad , Gopanpally , Hyderabad-500107 , Telangana , India .
| | - Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad , Gopanpally , Hyderabad-500107 , Telangana , India .
| | - Debabrata Dhara
- Tata Institute of Fundamental Research Hyderabad , Gopanpally , Hyderabad-500107 , Telangana , India .
| | - Pankaj Kalita
- School of Chemical Sciences , National Institute of Science Education and Research , HBNI , Bhubaneswar-752050 , India
| | | | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research Hyderabad , Gopanpally , Hyderabad-500107 , Telangana , India . .,Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur-208016 , India .
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie , Freie Universität Berlin , Fabeckstraße 34-36 , 14195 , Berlin , Germany .
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad , Gopanpally , Hyderabad-500107 , Telangana , India .
| |
Collapse
|
10
|
Oßwald S, Casper LA, Anders P, Schiebel E, Demeshko S, Winter RF. Electrochemical, Spectroelectrochemical, Mößbauer, and EPR Spectroscopic Studies on Ferrocenyl-Substituted Tritylium Dyes. Chemistry 2018; 24:12524-12538. [PMID: 29904938 DOI: 10.1002/chem.201802364] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/12/2018] [Indexed: 11/09/2022]
Abstract
Four monoferrocenyl tritylium derivatives with donor-substituted (OMe, NMe2 ) aryl rings are reported, along with their spectroscopic and electrochemical properties. All the complexes show a one-electron reduction and a quasi-reversible ferrocene oxidation at a very positive potential. Small quadrupole splittings, ΔEQ , in Mößbauer spectra agree with highly electron-deficient ferrocenes. Comparison of the experimental half-wave potentials for ferrocene oxidation, E1/2 (Fc/Fc+ ), with those estimated from established correlations of E1/2 (Fc/Fc+ ) with ΔEQ indicates that the E1/2 values of the anisyl-substituted congeners FcOMe+ and FcMeOMe+ are affected by Coulombic repulsion between the positive charges at the Fe ion and the neighboring methylium site. Electronic spectra are recorded and interpreted with the aid of quantum chemical calculations. UV/Vis spectroelectrochemical measurements as well as chemical reduction provide insight into the redox-induced color changes upon ferrocene oxidation or upon reduction to the neutral trityl radicals. The neutral radicals reversibly form EPR-silent dimers. This process is studied by temperature-dependent EPR spectroscopy, and thermodynamic data for their dimerization are determined. Experimental and quantum chemical data suggest that the dimers assume classical hexaarylethane structures as opposed to normal or "offset" Jacobson-Nauta-type structures.
Collapse
Affiliation(s)
- Steffen Oßwald
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Larissa A Casper
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Patrick Anders
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Eva Schiebel
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Serhiy Demeshko
- Fakultät für Chemie, Georg-August-Universität Göttingen, Tammannstrasse 4, 37077, Göttingen, Germany
| | - Rainer F Winter
- Fachbereich Chemie, Universität Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| |
Collapse
|
11
|
Oßwald S, Breimaier S, Linseis M, Winter RF. Polyelectrochromic Vinyl Ruthenium-Modified Tritylium Dyes. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Steffen Oßwald
- Fachbereich Chemie der Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Stefanie Breimaier
- Fachbereich Chemie der Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Michael Linseis
- Fachbereich Chemie der Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Rainer F. Winter
- Fachbereich Chemie der Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| |
Collapse
|
12
|
|
13
|
Pabel J, Faust M, Prehn C, Wörlein B, Allmendinger L, Höfner G, Wanner KT. Development of an (S)-1-{2-[Tris(4-methoxyphenyl)methoxy]ethyl}piperidine-3-carboxylic acid [(S)-SNAP-5114] Carba Analogue Inhibitor for Murine γ-Aminobutyric Acid Transporter Type 4. ChemMedChem 2012; 7:1245-55. [DOI: 10.1002/cmdc.201200126] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 04/05/2012] [Indexed: 11/06/2022]
|
14
|
Abstract
Many kinds of radicals are stable enough to isolate, handle, and store without any special precautions. The diversity in molecular architectures of these stable radicals is sufficiently large that the common factors governing radical stability/persistence, geometric and electronic structure, association/dimerization preferences, and reactivity have generally not been well articulated or appreciated. This review provides a survey of the major classes of stable or persistent organic/organomain group radicals with a view to presenting a unified description of the interdependencies between radical molecular structure and properties.
Collapse
Affiliation(s)
- Robin G Hicks
- Department of Chemistry, University of Victoria, PO Box 3065 STN CSC, Victoria, B.C. V8W 3V6, Canada.
| |
Collapse
|
15
|
Porter WW, Vaid TP. Doping of an organic molecular semiconductor by substitutional cocrystallization with a molecular n-dopant. ACTA ACUST UNITED AC 2007. [DOI: 10.1039/b610806g] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
16
|
Rajca A, Wongsriratanakul J, Rajca S. Organic Spin Clusters: Ferromagnetic Spin Coupling through a Biphenyl Unit in Polyarylmethyl Tri-, Penta-, Hepta-, and Hexadecaradicals. J Am Chem Soc 1997. [DOI: 10.1021/ja972378b] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrzej Rajca
- Contribution from the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Jirawat Wongsriratanakul
- Contribution from the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Suchada Rajca
- Contribution from the Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| |
Collapse
|
17
|
Ionic Dissociation of Carbon—Carbon σ Bonds in Hydrocarbons and the Formation of Authentic Hydrocarbon Salts. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 1995. [DOI: 10.1016/s0065-3160(08)60035-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
|