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Tsuzaki M, Ando S, Ishizuka T. Etherification via Aromatic Substitution on 1,3-Disubstituted Benzene Derivatives. J Org Chem 2022; 87:1357-1365. [PMID: 34978825 DOI: 10.1021/acs.joc.1c02670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, we developed a method for etherification via aromatic substitution at the ipso-position of an electron-withdrawing group (EWG) that exists at the meta-position of another EWG. To heighten the reactivity of the substitution reaction, we added a t-BuOK solution in tetrahydrofuran (THF) to a mixture of an aromatic substrate, an alcoholic nucleophile, and 18-crown-6-ether in dimethylformamide (DMF), which proved to be a particularly effective sequence. Under the conditions we established, aromatic substrates that are difficult to use for substitution reactions such as aryl fluorides activated with either a bromide or a chloride substituent were aptly converted to corresponding ether products at 25 °C. This reaction would potentially be useful to link an alcohol to an additional functional group through further chemical transformations via the use of a residual bromide or chloride substituent.
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Affiliation(s)
- Marina Tsuzaki
- Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Shin Ando
- Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Tadao Ishizuka
- Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
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2
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Anticancer activity of new benzofuroxan–imidazolone hybrids. MENDELEEV COMMUNICATIONS 2021. [DOI: 10.1016/j.mencom.2021.11.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Chugunova E, Frenna V, Consiglio G, Micheletti G, Boga C, Akylbekov N, Burilov A, Spinelli D. On the Nucleophilic Reactivity of 4,6-Dichloro-5-nitrobenzofuroxan with Some Aliphatic and Aromatic Amines: Selective Nucleophilic Substitution. J Org Chem 2020; 85:13472-13480. [PMID: 33153266 DOI: 10.1021/acs.joc.0c01502] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reaction rates for the nucleophilic aromatic substitution of 4,6-dichloro-5-nitrobenzofuroxan 1 with eight aliphatic amines (characterized by very different basicities/nucleophilicities) and three anilines have been measured in both methanol and toluene. The obtained rates have been related to the basicity (pKaH in water and Kb in benzene) or nucleophilicity (N Mayr constants) of the tested amines. The whole of the obtained kinetic data has furnished useful information on the high nucleophilic reactivity of benzofuroxan derivatives, which has been related essentially to two factors: the high electron-drawing ability/power of the condensed furoxan ring and the low aromatic character of the benzofuroxan system.
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Affiliation(s)
- Elena Chugunova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Akad. Arbuzov Street 8, 420088 Kazan, Tatarstan, Russia.,Laboratory of Plant Infectious Diseases, FRC Kazan Scientific Center of Russian Academy of Sciences, Lobachevskogo Street 2/31, 420111 Kazan, Tatarstan, Russia
| | - Vincenzo Frenna
- Department STEBICEF, Università di Palermo, Viale delle Scienze-Parco d'Orleans II, 90128 Palermo, Italy
| | - Giovanni Consiglio
- Department of Chemistry 'G. Ciamician', Alma Mater Studiorum-Università di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Gabriele Micheletti
- Department of Industrial Chemistry 'Toso Montanari', Alma Mater Studiorum-Università di Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy
| | - Carla Boga
- Department of Industrial Chemistry 'Toso Montanari', Alma Mater Studiorum-Università di Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy
| | - Nurgali Akylbekov
- Korkyt Ata Kyzylorda University, Aiteke bie Street, 29A, 120014 Kyzylorda, The Republic of Kazakhstan
| | - Alexander Burilov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Akad. Arbuzov Street 8, 420088 Kazan, Tatarstan, Russia.,Laboratory of Plant Infectious Diseases, FRC Kazan Scientific Center of Russian Academy of Sciences, Lobachevskogo Street 2/31, 420111 Kazan, Tatarstan, Russia
| | - Domenico Spinelli
- Department of Chemistry 'G. Ciamician', Alma Mater Studiorum-Università di Bologna, Via Selmi 2, 40126 Bologna, Italy
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Ando S, Tsuzaki M, Ishizuka T. Aryl Ether Syntheses via Aromatic Substitution Proceeding under Mild Conditions. J Org Chem 2020; 85:11181-11189. [PMID: 32786614 DOI: 10.1021/acs.joc.0c01250] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, mild conditions for aromatic substitutions during the syntheses of aryl ethers were developed. In the reaction conditions, the choices of solvent, base, and the sequence for the addition of the reagents proved important. A wide variety of alcohols were used directly as nucleophiles and smoothly reacted with aryl chlorides that possessed either a nitro or a cyano group at either the ortho- or para-position. Controlled experiments we performed suggested that the reaction underwent a charge-transfer process mediated by a combination of DMF and tert-BuOK.
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Affiliation(s)
- Shin Ando
- Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi Chuo-ku, Kumamoto 862-0973, Japan
| | - Marina Tsuzaki
- Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi Chuo-ku, Kumamoto 862-0973, Japan
| | - Tadao Ishizuka
- Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi Chuo-ku, Kumamoto 862-0973, Japan
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Semenyuk YP, Morozov PG, Burov ON, Kletskii ME, Lisovin AV, Kurbatov SV, Terrier F. Sequential SNAr and Diels–Alder reactivity of superelectrophilic 10π heteroaromatic substrates. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.03.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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6
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[3+2] Cycloaddition Reactions to Indolyl- and Pyrrolyl Derivatives of Dinitrobenzofurazan. Chem Heterocycl Compd (N Y) 2015. [DOI: 10.1007/s10593-015-1645-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Jovené C, Jacquet M, Marrot J, Bourdreux F, Kletsky ME, Burov ON, Gonçalves AM, Goumont R. Revisiting the Synthesis of 4,6-Difluorobenzofuroxan: A Study of Its Reactivity and Access to Fluorinated Quinoxaline Oxides. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402692] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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8
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Guesmi NE, Boubaker T, Goumont R. Single electron transfer in SNAr process: Reactions of 2,4,6-tris(trifluoromethanesulfonyl)anisole with anilines in dimethyl sulfoxide. PROGRESS IN REACTION KINETICS AND MECHANISM 2013. [DOI: 10.3184/146867813x13642226149123] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Second-order rate constants ( k1) have been measured spectrophotometrically for reactions of 2,4,6-tris(trifluoromethanesulfonyl)anisole 1 with 4-X-substituted anilines (X = OH, OCH3, CH3, H, I and Cl) 2a–f in dimethyl sulfoxide (DMSO) at 25 °C. The Hammett plot is nonlinear, i.e. the anilines having an electron-donating substituent exhibit positive deviations from the log k1 versus correlation. The Hammett plot consists of two intersecting straight lines, i.e. ρ=– 1.40 for electron-withdrawing substituents (X = I and Cl) while ρ=– 3.26 for electron-donating substituents (X = OH, OCH3 and CH3). The Brønsted-type plot is also nonlinear with a change in slope from a small value (βnuc=0.50) to a large value (βnuc = 1.29 at p Ka=4.58). This change could be interpreted in terms of a change in mechanism from a polar SNAr process to a single electron transfer. On the other hand, the experimental data show that the rate constants ( k1) values exhibit good correlation with the oxidation potentials ( E°) of the aniline nucleophiles and are consistent with the suggested mechanism.
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Affiliation(s)
- N. El Guesmi
- UR de Chimie Théorique et Réactivité, Faculté des Sciences de Monastir, 5019, Avenue de l'Environnement, Monastir, Tunisia
| | - T. Boubaker
- UR de Chimie Théorique et Réactivité, Faculté des Sciences de Monastir, 5019, Avenue de l'Environnement, Monastir, Tunisia
| | - R. Goumont
- UMR 8180, Institut Lavoisier de Versailles, Université de Versailles, 45, Avenue des Etats-Unis, 78035 Versailles Cedex, France
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Terrier F, Dust JM, Buncel E. Dual super-electrophilic and Diels–Alder reactivity of neutral 10π heteroaromatic substrates. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.12.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kurbatov S, Lakhdar S, Goumont R, Terrier F. Super-electrophilic 10π Heteroaromatics. New Mechanistic and Synthetic Applications. ORG PREP PROCED INT 2012. [DOI: 10.1080/00304948.2012.697701] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Lakhdar S, Terrier F, Vichard D, Berionni G, El Guesmi N, Goumont R, Boubaker T. The Diels-Alder reaction of 4,6-dinitrobenzofuroxan with 1-trimethylsilyloxybuta-1,3-diene: a case example of a stepwise cycloaddition. Chemistry 2010; 16:5681-90. [PMID: 20376824 DOI: 10.1002/chem.200903008] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The reaction of 4,6-dinitrobenzofuroxan (DNBF) with 1-trimethylsilyloxybuta-1,3-diene (8) is shown to afford a mixture of [2+4] diastereomeric cycloadducts (10, 11) through stepwise addition-cyclization pathways. Zwitterionic intermediate sigma-adduct 9, which is involved in the processes, has been successfully characterized by (1)H and (13)C NMR spectroscopy and UV/visible spectrophotometry in acetonitrile. A kinetic study has been carried out in this solvent that revealed that the rate of formation of 9 nicely fits the three-parameter equation log k=s(E+N) developed by Mayr to describe the feasibility of nucleophile-electrophile combinations. This significantly adds to the NMR spectroscopic evidence that the overall cycloadditions take place through a stepwise mechanism. The reaction has also been studied in dichloromethane and toluene. In these less polar solvents, the stability of 9 is not sufficient to allow direct characterization by spectroscopic methods, but a kinetic investigation supports the view that stepwise processes are still operating. An informative comparison of our reaction with previous interactions firmly identified as prototype stepwise cycloadditions is made on the basis of the global electrophilicity index, omega, defined by Parr within the density functional theory, and highlighted by Domingo et al. as a powerful tool for understanding Diels-Alder reactions.
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Affiliation(s)
- Sami Lakhdar
- Institut Lavoisier de Versailles, UMR 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France
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13
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Buncel E, Terrier F. Assessing the superelectrophilic dimension through σ-complexation, SNAr and Diels–Alder reactivity. Org Biomol Chem 2010; 8:2285-308. [DOI: 10.1039/b923983a] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Tatarov A, Kurbatov S, Borodkin G, Goumont R, Terrier F. SEAr–SNAr couplings of indolizines and related pyrrole derivatives with superelectrophilic nitrobenzoxadiazoles. Tetrahedron 2010. [DOI: 10.1016/j.tet.2009.11.071] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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El Guesmi N, Boubaker T, Goumont R, Terrier F. The Ambident Reactivity of 2,4,6-Tris(trifluoromethanesulfonyl)anisole in Methanol: Using the SO2CF3Group as a Tool to Reach the Superelectrophilic Dimension in σ-Complexation Processes. Chemistry 2009; 15:12018-29. [PMID: 19774563 DOI: 10.1002/chem.200901123] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nizar El Guesmi
- Unité de Recherche de Chimie Théorique et Réactivité, Faculté des Sciences de Monastir, Avenue de l'Environnement, 5019 Monastir, Tunisia
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Rodriguez-Dafonte P, Terrier F, Lakhdar S, Kurbatov S, Goumont R. Carbon Nucleophilicities of Indoles in SNAr Substitutions of Superelectrophilic 7-Chloro-4,6-dinitrobenzofuroxan and -benzofurazan. J Org Chem 2009; 74:3305-15. [DOI: 10.1021/jo900076r] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pedro Rodriguez-Dafonte
- Institut Lavoisier, UMR CNRS 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035-Versailles Cedex, France, and Department of Chemistry, Southern Federal University, 7 Zorge Street, 344090 Rostov-on-Don, Russian Federation
| | - François Terrier
- Institut Lavoisier, UMR CNRS 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035-Versailles Cedex, France, and Department of Chemistry, Southern Federal University, 7 Zorge Street, 344090 Rostov-on-Don, Russian Federation
| | - Sami Lakhdar
- Institut Lavoisier, UMR CNRS 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035-Versailles Cedex, France, and Department of Chemistry, Southern Federal University, 7 Zorge Street, 344090 Rostov-on-Don, Russian Federation
| | - Sergei Kurbatov
- Institut Lavoisier, UMR CNRS 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035-Versailles Cedex, France, and Department of Chemistry, Southern Federal University, 7 Zorge Street, 344090 Rostov-on-Don, Russian Federation
| | - Régis Goumont
- Institut Lavoisier, UMR CNRS 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035-Versailles Cedex, France, and Department of Chemistry, Southern Federal University, 7 Zorge Street, 344090 Rostov-on-Don, Russian Federation
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Boga C, Del Vecchio E, Forlani L, Goumont R, Terrier F, Tozzi S. Evidence for the intermediacy of Wheland-Meisenheimer complexes in SEAr reactions of aminothiazoles with 4,6-dinitrobenzofuroxan. Chemistry 2008; 13:9600-7. [PMID: 17868171 DOI: 10.1002/chem.200700669] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Reactions of DNBF with a series of 2-aminothiazoles (1 a-f) to afford thermodynamically stable C-bonded sigma-adducts have been investigated in acetonitrile. A most significant finding emerged on recording NMR spectra immediately after mixing of equimolar amounts of DNBF and the unsubstituted 2-aminothiazole (1 a) in Me2SO: namely, that the formation of 9 a is preceded by that of a short-lived intermediate species X. From the 1H NMR parameters characterizing this intermediate, as well as the dependence of its lifetime on the experimental conditions-the presence of excess DNBF over 1 a increases the lifetime of X while an excess of base (1 a) accelerates its conversion into 9 a--it is convincingly demonstrated that the structure of X combines the presence of a positively charged Wheland complex moiety (with regard to the thiazole ring) with that of a negatively charged Meisenheimer complex moiety (with regard to the benzofuroxan system). So far, only one intermediate of this type (noted WM) has been successfully characterized, in the reactions of DNBF with 1,3,5-tris(N,N-dialkylamino)benzenes. Among the key features supporting the intermediacy of X along the reaction coordinate leading to 9 a is the fact that the reactions of DNBF with 1 a in the presence of an alcohol (MeOH, EtOH, nPrOH) produce new adducts arising from the addition of an alcohol molecule to the thiazole moiety of WM-1 a. Reflecting the presence of three chiral centres, these species are formed as mixtures of several diastereomers that could all be characterized in their racemic forms in ethanol. These findings generalize the previous report on the formation of Wheland-Meisenheimer carbon-carbon complexes in homocyclic series.
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Affiliation(s)
- Carla Boga
- Department of Organic Chemistry A. Mangini, Facoltà di Chimica Industriale, ALMA MATER STUDIORUM-Università di Bologna, Viale Risorgimento, 4 40136 Bologna, Italy
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Cerecetto H, González M. Benzofuroxan and Furoxan. Chemistry and Biology. TOPICS IN HETEROCYCLIC CHEMISTRY 2007. [DOI: 10.1007/7081_2007_064] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Asghar BHM, Crampton MR. Carbanion reactivity; studies ofσ-adduct formation from benzyltriflone anions and 4-nitrobenzofurazan derivatives. J PHYS ORG CHEM 2007. [DOI: 10.1002/poc.1244] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kurbatov S, Tatarov A, Minkin V, Goumont R, Terrier F. Ring opening and ring closure in an indolizine structure activated through SNAr coupling with superelectrophilic 4,6-dinitrobenzofuroxan, an unusual intramolecular oxygen transfer from a N-oxide functionality. Chem Commun (Camb) 2006:4279-81. [PMID: 17047840 DOI: 10.1039/b608350a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coupling of superelectrophilic 4,6-dinitrobenzofuroxan with a pi-excessive indolizine structure affords a strongly dipolar substitution product which undergoes a facile but unusual rearrangement induced by an intramolecular oxygen atom transfer from the N-oxide functionality of the DNBF moiety.
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Affiliation(s)
- Sergey Kurbatov
- Department of Chemistry, Rostov State University, 7, Zorge St., 344090 Rostov-on-Don, Russia
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Moiseev AM, Balenkova ES, Nenajdenko VG. EWG-containing thiophene- and 2-thiolene-1,1-dioxides as promising electrophiles for organic synthesis. MENDELEEV COMMUNICATIONS 2006. [DOI: 10.1070/mc2006v016n04abeh002355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Boga C, Del Vecchio E, Forlani L, Mazzanti A, Todesco PE. Evidence for Carbon-Carbon Meisenheimer-Wheland Complexes between Superelectrophilic and Supernucleophilic Carbon Reagents. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200500238] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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Boga C, Del Vecchio E, Forlani L, Mazzanti A, Todesco PE. Evidence for Carbon-Carbon Meisenheimer-Wheland Complexes between Superelectrophilic and Supernucleophilic Carbon Reagents. Angew Chem Int Ed Engl 2005; 44:3285-9. [PMID: 15834853 DOI: 10.1002/anie.200500238] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Carla Boga
- Dipartimento di Chimica Organica A. Mangini, Facolta' di Chimica Industriale, Universita' di Bologna, Viale Risorgimento, 4-40136 Bologna, Italy
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Structural factors influencing the reaction rates of 4-aryloxy-7-nitrobenzofurazans with amino acids. OPEN CHEM 2004. [DOI: 10.2478/bf02482730] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AbstractAn interesting observation was made when studying the SNAr reaction between several 4-aryloxy-7-nitrobenzofurazans (2) and several amino acids leading to the apparition of detectable fluorescence from the substitution products3. Acidic amino acids reacted very slowly=while basic amino acids react fastest with2 having an unsubstituted phenyl or a 4-formyl-phenyl Ar group. Amongst neutral amino acids, proline reacts fastest at room temperature after 100 min. With2 having a methoxy-subtituted Ar group.
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