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Photochemical generation and characterization of the 5-endo-10,11-dihydrodibenzoazepine nitrenium ion. Photochem Photobiol Sci 2022; 21:1907-1914. [DOI: 10.1007/s43630-022-00267-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 07/04/2022] [Indexed: 10/17/2022]
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2
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Zhu S, Mao JH, Cheng JK, Xiang SH, Tan B. Discovery and organocatalytic enantioselective construction of axially chiral cyclohexadienylidene skeletons. Chem 2022. [DOI: 10.1016/j.chempr.2022.06.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Pradhan S, Roy S, Ghosh S, Chatterjee I. Regiodivergent Aromatic Electrophilic Substitution Using Nitrosoarenes in Hexafluoroisopropanol: A Gateway for Diarylamines and
p
‐Iminoquinones Synthesis. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201900788] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Suman Pradhan
- Department of ChemistryIndian Institute of Technology Ropar Nangal Road Rupnagar Punjab-140001 India
| | - Sourav Roy
- Department of ChemistryIndian Institute of Technology Ropar Nangal Road Rupnagar Punjab-140001 India
| | - Soumen Ghosh
- Department of ChemistryIndian Institute of Technology Ropar Nangal Road Rupnagar Punjab-140001 India
| | - Indranil Chatterjee
- Department of ChemistryIndian Institute of Technology Ropar Nangal Road Rupnagar Punjab-140001 India
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4
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Del Ponte G, Archanjo FC, Watanabe LY, Donate PM, Campos JM. Syntheses of non-aromatic medium and large rings synthesized via phenylnitrenium ions. ARAB J CHEM 2018. [DOI: 10.1016/j.arabjc.2016.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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5
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Huh CW, Aubé J. Aryl nitrenium ions from N-alkyl-N-arylamino-diazonium precursors: synthesis and reactivity. Chem Sci 2014. [DOI: 10.1039/c3sc52805g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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6
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Shamovsky I, Ripa L, Blomberg N, Eriksson LA, Hansen P, Mee C, Tyrchan C, O'Donovan M, Sjö P. Theoretical Studies of Chemical Reactivity of Metabolically Activated Forms of Aromatic Amines toward DNA. Chem Res Toxicol 2012; 25:2236-52. [DOI: 10.1021/tx300313b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Igor Shamovsky
- Department of Medicinal Chemistry, R&I iMed, AstraZeneca R&D, Pepparedsleden 1, S-431 83 Mölndal, Sweden
| | - Lena Ripa
- Department of Medicinal Chemistry, R&I iMed, AstraZeneca R&D, Pepparedsleden 1, S-431 83 Mölndal, Sweden
| | - Niklas Blomberg
- Department of Medicinal Chemistry, R&I iMed, AstraZeneca R&D, Pepparedsleden 1, S-431 83 Mölndal, Sweden
| | - Leif A. Eriksson
- Department of Chemistry and Molecular Biology, University of Gothenburg, S-412 96 Göteborg, Sweden
| | - Peter Hansen
- Department of Medicinal Chemistry, R&I iMed, AstraZeneca R&D, Pepparedsleden 1, S-431 83 Mölndal, Sweden
| | - Christine Mee
- Genetic Toxicology, AstraZeneca R&D, Alderley Park, Macclesfield, Cheshire, SK10 4TG, United Kingdom
| | - Christian Tyrchan
- Department of Medicinal Chemistry, CVGI iMed, AstraZeneca R&D, Pepparedsleden 1, S-431 83 Mölndal, Sweden
| | - Mike O'Donovan
- Genetic Toxicology, AstraZeneca R&D, Alderley Park, Macclesfield, Cheshire, SK10 4TG, United Kingdom
| | - Peter Sjö
- Department of Medicinal Chemistry, R&I iMed, AstraZeneca R&D, Pepparedsleden 1, S-431 83 Mölndal, Sweden
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7
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Winter AH, Gibson HH, Falvey DE. Carbazolyl nitrenium ion: electron configuration and antiaromaticity assessed by laser flash photolysis, trapping rate constants, product analysis, and computational studies. J Org Chem 2007; 72:8186-95. [PMID: 17892298 DOI: 10.1021/jo0708184] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Laser flash photolysis of 1-(carbazol-9-yl)-2,4,6-trimethylpyridinium tetrafluoroborate generates the carbazolyl nitrenium ion (tau = 333 ns, kobs = 3.0 x 106 M-1s-1) having absorption bands at 570 and 620 nm in CH3CN. The nitrenium ion is found to have reactivity comparable to structurally similar closed-shell diarylnitrenium ions, but spectroscopic evidence favors an open-shell singlet diradical assignment for the observed nitrenium ion. The carbazolyl nitrenium ion is also more reactive than diarylnitrenium ions as a likely result of antiaromatic character. Ab initio and hybrid DFT calculations were performed to address the degree of antiaromaticity in this and similar nitrenium ions through analysis of optimized geometries, nucleus independent chemical shifts, and isodesmic reactions.
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Affiliation(s)
- Arthur H Winter
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20740, USA
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8
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Thomas SI, Falvey DE. N,N-Di(4-halophenyl)nitrenium ions: nucleophilic trapping, aromatic substitution, and hydrogen atom transfer. J Org Chem 2007; 72:4626-34. [PMID: 17536861 DOI: 10.1021/jo062578i] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reactive intermediates N,N-di(4-chlorophenyl)nitrenium ion and N,N-di(4-bromophenyl)nitrenium ion were generated through photolysis of the corresponding N-amino(2,4,6,-collidinium) ions. The behavior of these diarylnitrenium ions was characterized by laser flash photolysis, analysis of the stable photoproducts, and ab initio calculations with density functional theory. The latter predict these species to have singlet ground states. The halogenated diarylnitrenium ions are significantly longer lived than the unsubstituted diphenylnitrenium ion. Specifically, cyclization to form carbazole derivatives occurs negligibly, if at all, with the halogenated derivatives. They do, however, carry out most of the characteristic reactions of singlet arylnitrenium ions, including combining with nucleophiles on the aryl rings, adding to arenes, and accepting electrons from readily oxidized traps. Interestingly these species also abstract H atoms from 1,4-cyclohexadiene and various phenol derivatives. The implication of the latter process in relation to the computed singlet-triplet energy gaps of ca. -12.5 kcal/mol is discussed.
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Affiliation(s)
- Selina I Thomas
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
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9
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Piech K, Bally T, Sikora A, Marcinek A. Mechanistic Aspects of the Oxidative and Reductive Fragmentation of N-Nitrosoamines: A New Method for Generating Nitrenium Cations, Amide Anions, and Aminyl Radicals. J Am Chem Soc 2007; 129:3211-7. [PMID: 17328546 DOI: 10.1021/ja066855e] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new method for investigating the mechanisms of nitric oxide release from NO donors under oxidative and reductive conditions is presented. Based on the fragmentation of N-nitrosoamines, it allows generation and spectroscopic characterization of nitrenium cations, amide anions, and aminyl radicals. X-irradiation of N-nitroso-N,N-diphenylamine 1 in Ar matrices at 10 K is found to yield the corresponding radical ions, which apparently undergo spontaneous loss of NO* under the conditions of this experiment (1*+ seems to survive partially intact, but not 1*-). One-electron reduction or oxidation of 1 is observed upon doping of the Ar matrix with DABCO, an efficient hole scavenger, or CH2Cl2, an electron scavenger, respectively. The resulting diphenylnitrenium cation, 2+, and the diphenylamide anion, 2-, were characterized by their full UV-vis and mid-IR spectra. The best spectra of 2+ and 2- were obtained if 1 was homolytically photodissociated to diphenylaminyl radical 2* and NO* prior to ionization. 2+ and 2- are bleached on irradiation at <340 nm to form 2* or, in part, 1. DFT and CCSD quantum chemical calculations predict that the dissociation of 1*+ and 1*- is slightly endothermic, a tendency which is partially reversed if one allows for complexation of the resulting 2+ (and, presumably, 2-) with NO*. The method described in this work should prove generally applicable to the generation and study of nitrenium cations and amide anions R2N+/- under matrix and ambient conditions (i.e., in solution).
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Affiliation(s)
- Krzysztof Piech
- Department of Chemistry, University of Fribourg, CH-1700 Fribourg, Switzerland
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10
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Kung AC, McIlroy SP, Falvey DE. Diphenylnitrenium ion: cyclization, electron transfer, and polymerization reactions. J Org Chem 2005; 70:5283-90. [PMID: 15960533 DOI: 10.1021/jo050598z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reactions of diphenylnitrenium ion were examined using laser flash photolysis (LFP), product analysis, and computational modeling using density functional theory (DFT). In the absence of trapping agents, diphenylnitrenium ion cyclizes to form carbazole. On the basis of laser flash photolysis experiments and DFT calculations it is argued that this process is a concerted cyclization/proton transfer that forms the H-4a tautomer of carbazole. Additional LFP experiments and product studies show that diphenylnitrenium ion reacts with electron-rich arenes (e.g., N,N-dimethylaniline, diphenylamine, and carbazole) through an initial one-electron transfer. The radical intermediates formed in this step then couple to form dimeric products. Secondary reactions between the diphenylnitrenium ion and these dimers results in the formation of oligomeric materials.
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Affiliation(s)
- Andrew C Kung
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742-2021, USA
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11
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Nitrenium Ions and Problem of Direct Electrophilic Amination of Aromatic Compounds. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2005. [DOI: 10.1007/s11178-005-0193-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Winter AH, Thomas SI, Kung AC, Falvey DE. Photochemical Generation of Nitrenium Ions from Protonated 1,1-Diarylhydrazines. Org Lett 2004; 6:4671-4. [PMID: 15575657 DOI: 10.1021/ol048250y] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Laser flash photolysis experiments, chemical trapping studies, and time-dependent density functional theory calculations demonstrate that photolysis of protonated 1,1-diarylhydrazines generates N,N-diarylnitrenium ions.
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Affiliation(s)
- Arthur H Winter
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
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13
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Facchini P, Grandinetti F. Concerning the reaction between singlet nitrenium ions and water: a computational investigation on competitive reaction paths. J Comput Chem 2003; 24:547-64. [PMID: 12632470 DOI: 10.1002/jcc.10182] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The reaction between singlet nitrenium ions XNH(+) (X = F and Cl) and H(2)O has been investigated by high-level of theory ab initio calculations. The geometries of the involved intermediates, transition structures, and dissociation products have been optimized at the MP2(full)/6-31G(d) level of theory, and accurate total energies have been obtained using the Gaussian-3 (G3) procedure. The reaction commences by the exothermic formation of the F-NH-OH(2) (+) and Cl-NH-OH(2) (+) intermediates, which are in turn able to undergo two distinct low-energy reaction paths, namely, the isomerization to the N-protonated isomers of the hydroxylamines F-NH-OH or Cl-NH-OH, and the eventual extrusion of HF or HCl. The competitive or alternative occurrence of these two processes strictly depends on the nature of the substituent X. In the reaction between FNH(+) and H(2)O, the energy gained in the formation of the complex F-NH-OH(2) (+) from the association between FNH(+) and H(2)O, 52.1 kcal mol(-1), is by far larger than the activation barrier for the loss of HF from F-NH-OH(2) (+), computed as 24.9 kcal mol(-1). In addition, the F-NH-OH(2) (+) intermediate requires 33.0 kcal mol(-1) to overcome the barrier for the isomerization to F-NH(2)-OH(+). Therefore, the reaction between FNH(+) and H(2)O is expected to occur practically exclusively by HF elimination with formation of the HN-OH(+) ionic product. On the other hand, for the reaction between ClNH(+) and H(2)O, it is not possible to get a definitive conclusion on the competitive or alternative occurrence of the two reaction paths. In fact, the transition structure involved in the elimination of HCl from Cl-NH-OH(2) (+) is only 3.4 kcal mol(-1) lower in energy than the transition structure for the isomerization of Cl-NH-OH(2) (+) to Cl-NH(2)-OH(+). In addition, the absolute values of the energy barriers of these two processes, 24.2 and 27.6 kcal mol(-1), respectively, are comparable with the energy gained in the formation of the complex Cl-NH-OH(2) (+) from the association between ClNH(+) and H(2)O, 24.0 kcal mol(-).1 Therefore, the ClNH(+) cation is predicted to react with water significantly slower than FNH(+).
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Affiliation(s)
- Paola Facchini
- Dipartimento di Scienze Ambientali and Istituto Nazionale di Fisica della Materia (INFM), Unità di Viterbo, Università della Tuscia, Largo dell' Università, 01100, Viterbo, Italy
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