1
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Kaur M, Cooper JC, Van Humbeck JF. Site-selective benzylic C-H hydroxylation in electron-deficient azaheterocycles. Org Biomol Chem 2024. [PMID: 38819259 DOI: 10.1039/d4ob00268g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
Benzylic C-H bonds can be converted into numerous functional groups, often by mechanisms that involve hydrogen atom transfer as the key bond breaking step. The abstracting species is most often an electrophilic radical, which makes these reactions best suited to electron-rich C-H bonds to achieve appropriate polarity matching. Thus, electron deficient systems such as pyridine and pyrimidine are relatively unreactive, and therefore underrepresented in substrate scopes. In this report, we describe a new method for heterobenzylic hydroxylation-essentially an unknown reaction in the case of pyrimidines-that makes use of an iodine(III) reagent to afford very high selectivity towards electron-deficient azaheterocycles in substrates with more than one reactive position and prevents over-oxidation to carbonyl products. The identification of key reaction byproducts supports a mechanism that involves radical coupling in the bond forming step.
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Affiliation(s)
- Milanpreet Kaur
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada.
| | - Julian C Cooper
- Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jeffrey F Van Humbeck
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada.
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2
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Holt E, Ruskin J, Garrison NG, Vemulapalli S, Lam W, Kiame N, Henriquez N, Borukhova F, Williams J, Dudding T, Lectka T. Photoactivated Pyridine Directed Fluorination through Hydrogen Atom Transfer. J Org Chem 2023. [PMID: 38033293 DOI: 10.1021/acs.joc.3c02146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
We have established hydrogen atom transfer (HAT) as the key player in a directed, photopromoted fluorination of pyridylic groups. The Lewis basic pyridyl nitrogen directs amine radical dication propagated HAT and Selectfluor fluorination of various ortho substituents in a highly regioselective manner with little to no side product formation. A variety of pyridines and quinolines were employed to showcase the directing capability of the nitrogen atom. Additionally, both experimental and computational data are provided that illuminate how this mechanism differs from and complements prior work in the area.
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Affiliation(s)
- Eric Holt
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Jonah Ruskin
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Nathaniel G Garrison
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Srini Vemulapalli
- Department of Chemistry, Brock University, St. Catharines, Ontario L2S3A1, Canada
| | - Winson Lam
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Neil Kiame
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Nicolas Henriquez
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Fanny Borukhova
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Jack Williams
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
| | - Travis Dudding
- Department of Chemistry, Brock University, St. Catharines, Ontario L2S3A1, Canada
| | - Thomas Lectka
- Department of Chemistry, Johns Hopkins University, 3400 North Charles St., Baltimore, Maryland 21218, United States
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3
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Wang X, Zhang X, Xue L, Wang Q, You F, Dai L, Wu J, Kramer S, Lian Z. Mechanochemical Synthesis of Aryl Fluorides by Using Ball Milling and a Piezoelectric Material as the Redox Catalyst. Angew Chem Int Ed Engl 2023; 62:e202307054. [PMID: 37523257 DOI: 10.1002/anie.202307054] [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: 05/19/2023] [Revised: 07/27/2023] [Accepted: 07/31/2023] [Indexed: 08/02/2023]
Abstract
Aryl fluorides are important structural motifs in many pharmaceuticals. Although the Balz-Schiemann reaction provides an entry to aryl fluorides from aryldiazonium tetrafluoroborates, it suffers from drawbacks such as long reaction time, high temperature, toxic solvent, toxic gas release, and low functional group tolerance. Here, we describe a general method for the synthesis of aryl fluorides from aryldiazonium tetrafluoroborates using a piezoelectric material as redox catalyst under ball milling conditions in the presence of Selectfluor. This approach effectively addresses the aforementioned limitations. Furthermore, the piezoelectric material can be recycled multiple times. Mechanistic investigations indicate that this fluorination reaction may proceed via a radical pathway, and Selectfluor plays a dual role as both a source of fluorine and a terminal reductant.
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Affiliation(s)
- Xiaohong Wang
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
| | - Xuemei Zhang
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
| | - Li Xue
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
| | - Qingqing Wang
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
| | - Fengzhi You
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
| | - Lunzhi Dai
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
| | - Jiagang Wu
- Department of Materials Science, Sichuan University, 610064, Chengdu, China
| | - Søren Kramer
- Department of Chemistry, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark
| | - Zhong Lian
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, Chengdu, P. R. China
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4
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Yamashita K, Fujiwara Y, Hamashima Y. Amide-Ligand-Promoted Silver-Catalyzed C-H Fluorination via Radical/Polar Crossover. J Org Chem 2023; 88:1865-1874. [PMID: 36688540 DOI: 10.1021/acs.joc.2c02575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We describe an efficient method for benzylic C-H fluorination via sequential hydrogen-atom transfer (HAT) and oxidative radical-polar crossover utilizing the Ag(I)/Selectfluor system. Amide ligands, such as benzamide and sulfonamide, substantially facilitate the processes leading to a carbocation intermediate, which subsequently reacts with nucleophilic fluorinating reagent to form a C-F bond. This protocol is applicable to the fluorination of all 1°, 2°, and 3° C-H bonds as well as to late-stage C-H fluorination of bioactive molecules.
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Affiliation(s)
- Kenji Yamashita
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Yuki Fujiwara
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Yoshitaka Hamashima
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
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5
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Chen Y, Yang B, Li QY, Lin YM, Gong L. Selectfluor®-enabled photochemical selective C(sp 3)-H(sulfonyl)amidation. Chem Commun (Camb) 2022; 59:118-121. [PMID: 36477311 DOI: 10.1039/d2cc05569d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Transition metal- and photosensitizer-free C(sp3)-H (sulfonyl)amidation reactions have been realized by employing Selectfluor® as a versatile reagent, functioning as a photoactive component, a HAT precursor and an oxidant. Various toluene derivatives, cycloalkanes, natural products and bioactive molecules can be converted into N-containing products under mild conditions in good yield and with high chemo- and site-selectivity.
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Affiliation(s)
- Yuehua Chen
- Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Boxuan Yang
- Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Qian-Yu Li
- Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Yu-Mei Lin
- Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Lei Gong
- Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. .,Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361005, China
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6
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Chiang JW, Lu PY, Han CC. Facile and Effective Syntheses of 2-Fluoro-3-alkoxythiophenes and Their Uses in Making Highly Regioregular Poly(3-alkoxythiophene)s via Transition-Metal-Free Cationic Chain-Growth Polymerization. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jo-Wen Chiang
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30013, ROC
| | - Po-Yu Lu
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30013, ROC
| | - Chien-Chung Han
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30013, ROC
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7
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Madani A, Anghileri L, Heydenreich M, Möller HM, Pieber B. Benzylic Fluorination Induced by a Charge-Transfer Complex with a Solvent-Dependent Selectivity Switch. Org Lett 2022; 24:5376-5380. [PMID: 35848228 PMCID: PMC9344467 DOI: 10.1021/acs.orglett.2c02050] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
![]()
We present a divergent strategy for the fluorination
of phenylacetic
acid derivatives that is induced by a charge-transfer complex between
Selectfluor and 4-(dimethylamino)pyridine. A comprehensive investigation
of the conditions revealed a critical role of the solvent on the reaction
outcome. In the presence of water, decarboxylative fluorination through
a single-electron oxidation is dominant. Non-aqueous conditions result
in the clean formation of α-fluoro-α-arylcarboxylic acids.
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Affiliation(s)
- Amiera Madani
- Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Lucia Anghileri
- Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Matthias Heydenreich
- Institute of Chemistry/Analytical Chemistry, University of Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany
| | - Heiko M Möller
- Institute of Chemistry/Analytical Chemistry, University of Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany
| | - Bartholomäus Pieber
- Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany
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8
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Baker SI, Yaghoubi M, Bidwell SL, Pierce SL, Hratchian HP, Baxter RD. Enhanced Reactivity for Aromatic Bromination via Halogen Bonding with Lactic Acid Derivatives. J Org Chem 2022; 87:8492-8502. [PMID: 35709498 DOI: 10.1021/acs.joc.2c00611] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a new method for regioselective aromatic bromination using lactic acid derivatives as halogen bond acceptors with N-bromosuccinimide (NBS). Several structural analogues of lactic acid affect the efficiency of aromatic brominations, presumably via Lewis acid/base halogen-bonding interactions. Rate comparisons of aromatic brominations demonstrate the reactivity enhancement available via catalytic additives capable of halogen bonding. Computational results demonstrate that Lewis basic additives interact with NBS to increase the electropositive character of bromine prior to electrophilic transfer. An optimized procedure using catalytic mandelic acid under aqueous conditions at room temperature was developed to promote aromatic bromination on a variety of arene substrates with complete regioselectivity.
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Affiliation(s)
- Sarah I Baker
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Mahshid Yaghoubi
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Samantha L Bidwell
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Savannah L Pierce
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Hrant P Hratchian
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Ryan D Baxter
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
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9
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Harry SA, Vemulapalli S, Dudding T, Lectka T. Rational Computational Design of Systems Exhibiting Strong Halogen Bonding Involving Fluorine in Bicyclic Diamine Derivatives. J Org Chem 2022; 87:8413-8419. [PMID: 35658438 DOI: 10.1021/acs.joc.2c00497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Perhaps the most controversial and rare aspect of the halogen bonding interaction is the potential of fluorine in compounds to serve as a halogen bond donor. In this note, we provide clear and convincing examples of hypothetical molecules in which fluorine is strongly halogen bonding in a metastable state. Of particular note is a polycyclic system inspired by Selectfluor, which has been controversially proposed to engage in halogen bonding.
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Affiliation(s)
- Stefan Andrew Harry
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Srini Vemulapalli
- Department of Chemistry, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Travis Dudding
- Department of Chemistry, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Thomas Lectka
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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10
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Capilato JN, Harry SA, Siegler MA, Lectka T. Spectroscopic and Crystallographic Characterization of the R 3 N + -C-H⋅⋅⋅X Interaction. Chemistry 2022; 28:e202103922. [PMID: 35133051 DOI: 10.1002/chem.202103922] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Indexed: 01/11/2023]
Abstract
As appreciation for nonclassical hydrogen bonds has progressively increased, so have efforts to characterize these interesting interactions. Whereas several kinds of C-H hydrogen bonds have been well-studied, much less is known about the R3 N+ -C-H⋅⋅⋅X variety. Herein, we present crystallographic and spectroscopic evidence for the existence of these interactions, with special relevance to Selectfluor chemistry. Of particular note is the propensity for Lewis bases to engage in nonclassical hydrogen bonding over halogen bonding with the electrophilic F atom of Selectfluor. Further, the first examples of 1 H NMR experiments detailing R3 N+ -C-H⋅⋅⋅X (X=O, N) hydrogen bonds are described.
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Affiliation(s)
- Joseph N Capilato
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
| | - Stefan A Harry
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
| | - Maxime A Siegler
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
| | - Thomas Lectka
- Department of Chemistry, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
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11
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12
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Wang Z, Zeng L, He C, Duan C. Photocatalytic C-H Activation with Alcohol as a Hydrogen Atom Transfer Agent in a 9-Fluorenone Based Metal-Organic Framework. ACS APPLIED MATERIALS & INTERFACES 2021; 13:25898-25905. [PMID: 34043310 DOI: 10.1021/acsami.1c03098] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Hydrogen atom transfer (HAT) has become an attractive strategy for the activation of hydrocarbon feedstocks. Alcohols, as inexpensive and efficient hydrogen transfer reagents, have limited application in C-H functionalization due to the difficulty in the alkoxy radical acquisition. 9-Fluorenone moieties were incorporated into the metal-organic framework (MOF) as a photocatalyst; through the formation of hydrogen bonds between the carbonyl group of a ligand and alcohol, alkoxy radicals could be obtained by the visible-light-driven oxidation of 2,2,2-trichloroethanol via proton-coupled electron transfer (PCET). Effectively photocatalyzed intermolecular coupling reactions between phenyl vinyl sulfone and aldehyde or cyclic ether were realized through the HAT pathway. Compared to homogeneous catalysts, the heterogeneous MOF photocatalyst improved the catalytic efficiency and could be recycled at least five times. The microenvironment of the Zn-OFDC channel was beneficial for the formation of hydrogen bonds and stability of alkoxy radicals.
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Affiliation(s)
- Zhonghe Wang
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China
| | - Le Zeng
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China
| | - Cheng He
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China
| | - Chunying Duan
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China
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13
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Galloway JD, Sarabia C, Fettinger JC, Hratchian HP, Baxter RD. Versatile New Reagent for Nitrosation under Mild Conditions. Org Lett 2021; 23:3253-3258. [PMID: 33844555 DOI: 10.1021/acs.orglett.1c00637] [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
Here we report a new chemical reagent for transnitrosation under mild experimental conditions. This new reagent is stable to air and moisture across a broad range of temperatures and is effective for transnitrosation in multiple solvents. Compared with traditional nitrosation methods, our reagent shows high functional group tolerance for substrates that are susceptible to oxidation or reversible transnitrosation. Several challenging nitroso compounds are accessed here for the first time, including 15N isotopologues. X-ray data confirm that two rotational isomers of the reagent are configurationally stable at room temperature, although only one isomer is effective for transnitrosation. Computational analysis describes the energetics of rotamer interconversion, including interesting geometry-dependent hybridization effects.
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Affiliation(s)
- Jordan D Galloway
- Department of Chemistry and Chemical Biology, University of California, Merced, Merced, California 95343, United States
| | - Cristian Sarabia
- Department of Chemistry and Chemical Biology, University of California, Merced, Merced, California 95343, United States
| | - James C Fettinger
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Hrant P Hratchian
- Department of Chemistry and Chemical Biology, University of California, Merced, Merced, California 95343, United States
| | - Ryan D Baxter
- Department of Chemistry and Chemical Biology, University of California, Merced, Merced, California 95343, United States
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14
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Vincent É, Brioche J. Synthesis of Alkyl Fluorides by Silver‐Catalyzed Radical Decarboxylative Fluorination of Cesium Oxalates. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100344] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Émilie Vincent
- INSA Rouen UNIROUEN CNRS COBRA (UMR 6014) Normandie University 76000 Rouen France
| | - Julien Brioche
- INSA Rouen UNIROUEN CNRS COBRA (UMR 6014) Normandie University 76000 Rouen France
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15
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Chen W, Li HJ, Liu M, Gong PX, Wu YC. Synthesis of difluorinated 3-oxo- N,3-diarylpropanamides from 4-arylamino coumarins mediated by Selectfluor. Org Chem Front 2021. [DOI: 10.1039/d1qo01273h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An expeditious approach to synthesize difluorinated 3-oxo-N,3-diarylpropanamides from 4-arylamino coumarins has been accomplished in the presence of Selectfluor, which plays the dual role of a mild oxidant and a source of fluorine.
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Affiliation(s)
- Weiqiang Chen
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai 264209, P. R. China
| | - Hui-Jing Li
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai 264209, P. R. China
| | - Mei Liu
- China Building Material Test & Certification Group Zibo Co., Ltd, Zibo 255000, P. R. China
| | - Pi-Xian Gong
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai 264209, P. R. China
| | - Yan-Chao Wu
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai 264209, P. R. China
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16
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Halogen bonding interactions in the XC 5H 4N···YCF 3 (X = CH 3, H, Cl, CN, NO 2; Y = Cl, Br, I) complexes. J Mol Model 2020; 26:344. [PMID: 33205319 DOI: 10.1007/s00894-020-04606-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 11/08/2020] [Indexed: 10/23/2022]
Abstract
The noncovalent interactions between the σ-hole region outside the halogen atom and the nitrogen atom of pyridine and its para-substituted derivatives are the focus of this work. Based on the analyses of the electrostatic potentials, YCF3 (Y = Cl, Br, I) act as halogen bond donors, XC5H4N (X = CH3, H, Cl, CN, NO2) act as halogen bond acceptors, and the binary halogen-bonded complexes XC5H4N···YCF3 have been designed and investigated by B3LYP-D3/aug-cc-pVDZ calculations together with the aug-cc-pVDZ-PP basis set for iodine. When the halogen bond acceptor remains unchanged, the interactions between C5H5N and YCF3 (Y = Cl, Br, I) increase with the order of Y = Cl, Br, and I. When the halogen donor ICF3 is fixed, the halogen bonding interactions decrease along the sequence of X = CH3, H, Cl, CN, NO2. Therefore, the halogen bond of the CH3C5H4N···ICF3 complex is the strongest. The interactions between Lewis acid YCF3 (Y = Cl, Br, I) and pyridine and para-substituted pyridine are closed-shell and noncovalent interactions. On the one hand, when the halogen bond acceptor XC5H4N is fixed, with the increase of halogen atomic number, the strength of halogen bond increases; on the other hand, when the halogen bond donor ICF3 is fixed, as the electron-withdrawing ability of the electron-withdrawing group (X) increases, the halogen bond gradually weakens.
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17
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Aguilar Troyano FJ, Merkens K, Gómez‐Suárez A. Selectfluor® Radical Dication (TEDA
2+.
) – A Versatile Species in Modern Synthetic Organic Chemistry. ASIAN J ORG CHEM 2020. [DOI: 10.1002/ajoc.202000196] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
| | - Kay Merkens
- Organic ChemistryBergische Universität Wuppertal Gaußstr. 20 42119 Wuppertal Germany
| | - Adrián Gómez‐Suárez
- Organic ChemistryBergische Universität Wuppertal Gaußstr. 20 42119 Wuppertal Germany
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18
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Abstract
Halonium ions are particularly strong halogen bond donors, and are accordingly valuable tools for a variety of fields, such as supramolecular and synthetic organic chemistry.
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Affiliation(s)
- Lotta Turunen
- Department of Chemistry – BMC
- Uppsala University
- SE-751 23 Uppsala
- Sweden
| | - Máté Erdélyi
- Department of Chemistry – BMC
- Uppsala University
- SE-751 23 Uppsala
- Sweden
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19
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20
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21
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Yu W, Wu W, Jiang H. Copper‐Catalyzed Benzylic C—H Functionalization, Oxidation and Cyclization of Methylarenes: Direct Access to 2‐Arylbenzothiazoles. CHINESE J CHEM 2019. [DOI: 10.1002/cjoc.201900340] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Wentao Yu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical EngineeringSouth China University of Technology Guangzhou Guangdong 510640 China
| | - Wanqing Wu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical EngineeringSouth China University of Technology Guangzhou Guangdong 510640 China
| | - Huanfeng Jiang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical EngineeringSouth China University of Technology Guangzhou Guangdong 510640 China
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Galloway JD, Mai DN, Baxter RD. Radical Benzylation of Quinones via C–H Abstraction. J Org Chem 2019; 84:12131-12137. [DOI: 10.1021/acs.joc.9b01004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jordan D. Galloway
- Department of Chemistry, Chemical Biology, University of California, 5200 North Lake Road, Merced, California 95343, United States
| | - Duy N. Mai
- Department of Chemistry, Chemical Biology, University of California, 5200 North Lake Road, Merced, California 95343, United States
| | - Ryan D. Baxter
- Department of Chemistry, Chemical Biology, University of California, 5200 North Lake Road, Merced, California 95343, United States
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