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Chu XQ, Ge D, Cui YY, Shen ZL, Li CJ. Desulfonylation via Radical Process: Recent Developments in Organic Synthesis. Chem Rev 2021; 121:12548-12680. [PMID: 34387465 DOI: 10.1021/acs.chemrev.1c00084] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
As the "chemical chameleon", sulfonyl-containing compounds and their variants have been merged with various types of reactions for the efficient construction of diverse molecular architectures by taking advantage of their incredible reactive flexibility. Currently, their involvement in radical transformations, in which the sulfonyl group typically acts as a leaving group via selective C-S, N-S, O-S, S-S, and Se-S bond cleavage/functionalization, has facilitated new bond formation strategies which are complementary to classical two-electron cross-couplings via organometallic or ionic intermediates. Considering the great influence and synthetic potential of these novel avenues, we summarize recent advances in this rapidly expanding area by discussing the reaction designs, substrate scopes, mechanistic studies, and their limitations, outlining the state-of-the-art processes involved in radical-mediated desulfonylation and related transformations. With a specific emphasis on their synthetic applications, we believe this review will be useful for medicinal and synthetic organic chemists who are interested in radical chemistry and radical-mediated desulfonylation in particular.
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Affiliation(s)
- Xue-Qiang Chu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Danhua Ge
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Yan-Ying Cui
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Zhi-Liang Shen
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Chao-Jun Li
- Department of Chemistry and FQRNT Centre for Green Chemistry and Catalysis, McGill University, Montreal, Quebec H3A 0B8, Canada
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Recio J, Filace F, Gala E, Pérez-Redondo A, Álvarez-Builla J, Burgos C. Studies on the preparation of aminobipyridines and bipyridine sultams via an intramolecular free radical pathway. RSC Adv 2020; 10:10447-10451. [PMID: 35492915 PMCID: PMC9050412 DOI: 10.1039/d0ra02026e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 03/04/2020] [Indexed: 12/17/2022] Open
Abstract
A variety of aminated bipyridines and bipyridine sultams are prepared by intramolecular radical [1,5]-ipso and [1,6]-ortho substitutions, using a sulfonamide as a linker to connect the pyridyl radical to the pyridine under attack. For the cases studied, different regiochemistries are observed depending on the initial position of the sulfonamide linker. Results show that intramolecular radical [1,5]-ipso and [1,6]-ortho substitutions offer a method for the preparation of aminobipyridines or bipyridine sultams.![]()
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Affiliation(s)
- Javier Recio
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigación Química “Andrés M. del Río” (IQAR)
- Universidad de Alcalá
- 28805-Alcalá de Henares
- Spain
| | - Fabiana Filace
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigación Química “Andrés M. del Río” (IQAR)
- Universidad de Alcalá
- 28805-Alcalá de Henares
- Spain
| | - Elena Gala
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigación Química “Andrés M. del Río” (IQAR)
- Universidad de Alcalá
- 28805-Alcalá de Henares
- Spain
| | - Adrián Pérez-Redondo
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigación Química “Andrés M. del Río” (IQAR)
- Universidad de Alcalá
- 28805-Alcalá de Henares
- Spain
| | - Julio Álvarez-Builla
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigación Química “Andrés M. del Río” (IQAR)
- Universidad de Alcalá
- 28805-Alcalá de Henares
- Spain
| | - Carolina Burgos
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigación Química “Andrés M. del Río” (IQAR)
- Universidad de Alcalá
- 28805-Alcalá de Henares
- Spain
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Xue Z, Zhang W, Yan M, Liu J, Wang B, Xia Y. Pyrolysis products and thermal degradation mechanism of intrinsically flame-retardant carrageenan fiber. RSC Adv 2017. [DOI: 10.1039/c7ra01076a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Carrageenan fiber (CAF) was prepared by a wet spinning method to develop an excellent flame-retardant material.
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Affiliation(s)
- Zhixin Xue
- College of Chemistry and Chemical Engineering
- Qingdao University
- Qingdao 266071
- China
- Research Institute of Marine Fiber Novel Materials
| | - Weiwei Zhang
- College of Chemistry and Chemical Engineering
- Qingdao University
- Qingdao 266071
- China
- Research Institute of Marine Fiber Novel Materials
| | - Miao Yan
- College of Chemistry and Chemical Engineering
- Qingdao University
- Qingdao 266071
- China
- Research Institute of Marine Fiber Novel Materials
| | - Jingjing Liu
- College of Chemistry and Chemical Engineering
- Qingdao University
- Qingdao 266071
- China
- Research Institute of Marine Fiber Novel Materials
| | - Bingbing Wang
- Research Institute of Marine Fiber Novel Materials
- Qingdao University
- Qingdao 266071
- China
- Yantai Tayho Advanced Materials Group Co., Ltd
| | - Yanzhi Xia
- Research Institute of Marine Fiber Novel Materials
- Qingdao University
- Qingdao 266071
- China
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Ujjainwalla F, da Mata MLE, Pennell AM, Escolano C, Motherwell WB, Vázquez S. Synthesis of biaryls via intramolecular free radical ipso-substitution reactions. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.07.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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5
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Affiliation(s)
- Chang-Liang Sun
- Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Green Chemistry Center, Peking University , 202 Chengfu Road, 098#, Beijing 100871, China
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Li Y, Ding Q, Qiu G, Wu J. Synthesis of benzosultams via an intramolecular sp2C–H bond amination reaction of o-arylbenzenesulfonamides under metal-free conditions. Org Biomol Chem 2014; 12:149-55. [DOI: 10.1039/c3ob41810c] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Bheeter CB, Bera JK, Doucet H. Palladium-Catalysed Intramolecular Direct Arylation of 2-Bromobenzenesulfonic Acid Derivatives. Adv Synth Catal 2012. [DOI: 10.1002/adsc.201200793] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Gao J, Hedman C, Liu C, Guo T, Pedersen JA. Transformation of sulfamethazine by manganese oxide in aqueous solution. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:2642-51. [PMID: 22243052 DOI: 10.1021/es202492h] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The transformation of the sulfonamide antimicrobial sulfamethazine (SMZ) by a synthetic analogue of the birnessite-family mineral vernadite (δ-MnO(2)) was studied. The observed pseudo-first-order reaction constants (k(obs)) decreased as the pH increased from 4.0 to 5.6, consistent with the decline in δ-MnO(2) reduction potential with increasing pH. Molecular oxygen accelerated SMZ transformation by δ-MnO(2) and influenced the transformation product distribution. Increases in the Na(+) concentration produced declines in k(obs). Transformation products identified by tandem mass spectrometry and the use of (13)C-labeled SMZ included an azo dimer self-coupling product and SO(2) extrusion products. Product analysis and density functional theory calculations are consistent with surface precursor complex formation followed by single-electron transfer from SMZ to δ-MnO(2) to produce SMZ radical species. Sulfamethazine radicals undergo further transformation by at least two pathways: radical-radical self-coupling or a Smiles-type rearrangement with O addition and then extrusion of SO(3). Experiments conducted in H(2)(18)O or in the presence of (18)O(2)(aq) demonstrated that oxygen both from the lattice of as-synthesized δ-MnO(2) and initially present as dissolved oxygen reacted with SMZ. The study results suggest that the oxic state and pH of soil and sediment environments can be expected to influence manganese oxide-mediated transformation of sulfonamide antimicrobials.
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Affiliation(s)
- Juan Gao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, People's Republic of China
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Castillo RR, Burgos C, Vaquero JJ, Alvarez-Builla J. Radical Intramolecular Arylation of Pyridinium Salts: A Straightforward Entry to 7-Hydroxypyrido[2,1-a]isoquinolinylium Salts. European J Org Chem 2010. [DOI: 10.1002/ejoc.201001071] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Wang T, Nibbering NMM, Bowie JH. The gas phase Smiles rearrangement of anions PhO(CH2)nO− (n = 2–4). A joint theoretical and experimental approach. Org Biomol Chem 2010; 8:4080-4. [DOI: 10.1039/c0ob00064g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Lu SC, Zhang XX, Shi ZJ, Ren YW, Li B, Zhang W. Intramolecular Photochemical Cross-Coupling Reactions of 3-Acyl-2-haloindoles and 2-Chloropyrrole-3-carbaldehydes with Substituted Benzenes. Adv Synth Catal 2009. [DOI: 10.1002/adsc.200900540] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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12
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Maclean MJ, Walker S, Wang T, Eichinger PCH, Sherman PJ, Bowie JH. Diagnostic fragmentations of adducts formed between carbanions and carbon disulfide in the gas phase. A joint experimental and theoretical study. Org Biomol Chem 2009; 8:371-7. [PMID: 20066272 DOI: 10.1039/b916477d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Selected carbanions react with carbon disulfide in a modified LCQ ion trap mass spectrometer to form adducts, which when collisionally activated, decompose by processes which in some cases identify the structures of the original carbanions. For example (i) C(6)H(5)(-) + CS(2)--> C(6)H(5)CS(2)(-)--> C(6)H(5)S(-) + CS, occurs through a 3-membered ring ipso transition state, and (ii) the reaction between C(6)H(5)CH(2)(-) and CS(2) gives an adduct which loses H(2)S, whereas the adduct(s) formed between o-CH(3)C(6)H(5)(-) and CS(2) loses H(2)S and CS. Finally, it is shown that decarboxylation of C(6)H(5)CH(2)CH(2)CO(2)(-) produces the beta-phenylethyl anion (PhCH(2)CH(2)(-)), and that this thermalized anion reacts with CS(2) to form C(6)H(5)CH(2)CH(2)CS(2)(-) which when energized fragments specifically by the process C(6)H(5)CH(2)CH(2)CS(2)(-)--> C(6)H(5)CH(2)(-)CHC(S)SH --> [(C(6)H(5)CH(2)CH[double bond, length as m-dash]C[double bond, length as m-dash]S) (-)SH] --> C(6)H(5)CH(2)CCS(-) + H(2)S. Experimental findings of processes (ii) and (iii) were aided by deuterium labelling studies, and all reaction profiles were studied by theoretical calculations at the UCCSD(T)/6-31+G(d,p)//B3LYP/6-31+G(d,p) level of theory unless indicated to the contrary.
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Affiliation(s)
- Micheal J Maclean
- Department of Chemistry, The University of Adelaide, South Australia, 5005, Australia
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13
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3-exo-tet Cyclization of 2,2-disubstituted 1,3-dihalopropanes with indium in aqueous and ionic liquid solvent system. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.06.123] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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Ohkita T, Tsuchiya Y, Togo H. Radical 3-exo-tet cyclization of 1,3-dihalopropanes with SmI2 to form cyclopropanes. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.05.081] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Chapter 1 Recent progress in the chemistry of 2,1-benzothiazines. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0959-6380(08)80003-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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16
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Bowman WR, Storey JMD. Synthesis using aromatic homolytic substitution—recent advances. Chem Soc Rev 2007; 36:1803-22. [PMID: 18213987 DOI: 10.1039/b605183a] [Citation(s) in RCA: 258] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- W Russell Bowman
- Department of Chemistry, Loughborough University, Loughborough, Leicester, UK.
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Clyne MA, Aldabbagh F. Photochemical intramolecular aromatic substitutions of the imidazol-2-yl radical are superior to those mediated by Bu3SnH. Org Biomol Chem 2005; 4:268-77. [PMID: 16391769 DOI: 10.1039/b512729g] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Six-membered photochemical cyclisations of 2-iodo-N-(2-arylethyl)imidazoles proceeded regioselectively in higher yields than the equivalent tin hydride-mediated reactions. The decrease in yield of cyclisation products, 5,6-dihydroimidazo[2,1-a]isoquinolines containing strongly deactivating substituents on the aryl ring confirmed the electrophilic nature of the sigma-imidazol-2-yl radicals. The seven-membered cyclisation was only successful under photochemical conditions, as radical reduction occurred with tin hydride. Nitration of 5,6-dihydroimidazo[2,1-a]isoquinoline with nitric/sulfuric acid occurred at the 2- and 8-positions.
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Affiliation(s)
- Mairéad A Clyne
- Department of Chemistry, National University of Ireland, Galway, Ireland
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18
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Sakuma D, Togo H. Facile preparation of cyclopropanes from 2-iodoethyl-substituted olefins and 1,3-dihalopropanes with zinc powder. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.07.103] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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19
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Pyridinium N-2′-pyridylaminide: synthesis of 3-aryl-2-aminopyridines through an intramolecular radical process. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.09.099] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Núñez A, Sánchez A, Burgos C, Alvarez-Builla J. Synthesis of carbo- and heterobiaryls by intermolecular radical addition of aryl bromides onto aromatic solvents. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.05.038] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Ohno H, Okumura M, Maeda SI, Iwasaki H, Wakayama R, Tanaka T. Samarium(II)-Promoted Radical Spirocyclization onto an Aromatic Ring. J Org Chem 2003; 68:7722-32. [PMID: 14510548 DOI: 10.1021/jo034767w] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Samarium(II)-mediated spirocyclization onto an aromatic ring was achieved by the reaction of methyl 4-(4-oxoalkyl)benzoates with SmI(2) in the presence of i-PrOH and HMPA, yielding methyl 1-alkyl-1-hydroxyspiro[4.5]dec-6-ene-8-carboxylates in moderate to high yields. Utilizing this chemistry, spiro[3.5] and -[5.5] systems, and sterically congested spiro[4.5] systems, were easily synthesized. For the successful conversion, appropriate activation of the aromatic ring has proven to be extremely important: while an ester or amide functionality on the aromatic ring can promote the spirocyclization, a sulfonamide substituent causes ortho cyclization.
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Affiliation(s)
- Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
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Sugi M, Sakuma D, Togo H. Zinc- and Indium-Mediated Ring-Expansion Reaction of α-Halomethyl Cyclic β-Keto Esters in Aqueous Alcohol. J Org Chem 2003; 68:7629-33. [PMID: 14510535 DOI: 10.1021/jo030092l] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Radical ring-expansion reaction of various alpha-halomethyl cyclic beta-keto esters and alpha-halomethyl benzocyclic beta-keto esters and chain-extension reaction of alpha-halomethyl beta-keto esters with zinc powder and indium powder in refluxing aqueous alcohol were carried out to generate the corresponding ring-expansion and chain-extension products. As the results indicate, it was found zinc powder was more effective than indium powder to give the corresponding ring-expanded products in quite good yields. Moreover, the addition of zinc bromide as Lewis acid showed an increase of the yields, depending on the substrates. The present reaction conditions are highly effective, simple, and environmentally friendly.
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Affiliation(s)
- Masaaki Sugi
- Graduate School of Science and Technology, and Department of Chemistry, Faculty of Science, Chiba University, Yayoi-cho 1-33, Inage-ku, Chiba 263-8522, Japan
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Shintou T, Kikuchi W, Mukaiyama T. Efficient Method for the Preparation of Carboxylic Acid Alkyl Esters or Alkyl Phenyl Ethers by a New-Type of Oxidation–Reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone and Alkoxydiphenylphosphines. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2003. [DOI: 10.1246/bcsj.76.1645] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Ohno H, Wakayama R, Maeda SI, Iwasaki H, Okumura M, Iwata C, Mikamiyama H, Tanaka T. Radical cyclization by ipso substitution of the methoxy group: considerable effect of HMPA on samarium-mediated cyclization. J Org Chem 2003; 68:5909-16. [PMID: 12868925 DOI: 10.1021/jo0343174] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alkyl radicals generated by treatment of thiocarbamates of conformationally favorable 3-alkyl-3-arylpropan-1-ols with tris(trimethylsilyl)silane and AIBN efficiently undergo intramolecular ipso substitution of the methoxy group, yielding the corresponding cyclized products. In contrast, either conformationally favorable or flexible 1-arylalkan-3- or 4-ones easily cyclize into five- or six-membered condensed rings by treatment with SmI(2) via ketyl radical intermediates. The addition of HMPA as cosolvent dramatically changes the cyclization mode of the SmI(2)-induced reaction, and the para-cyclization products are exclusively formed. This "HMPA effect" can be rationalized by the strong chelating ability of HMPA with the samarium atom.
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Affiliation(s)
- Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
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25
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Zhang W, Pugh G. Free radical reactions for heterocycle synthesis. Part 6: 2-Bromobenzoic acids as building blocks in the construction of nitrogen heterocycles. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00381-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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Liang JL, Yuan SX, Chan PWH, Che CM. Rhodium(II,II) dimer as an efficient catalyst for aziridination of sulfonamides and amidation of steroids. Org Lett 2002; 4:4507-10. [PMID: 12465924 DOI: 10.1021/ol0270475] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Unsaturated sulfonamides underwent direct intramolecular aziridination catalyzed by Rh(2)(OAc)(4) with PhI(OAc)(2) and Al(2)O(3) to give the corresponding aziridine products in excellent yields (up to 98%) and with good to excellent conversions. High turnovers (up to 1375) were achieved. The intermolecular rhodium-catalyzed amidation of cholesteryl acetate with PhI=NTs or PhI(OAc)(2)/NH(2)R as the nitrogen source exhibited both excellent regio- and alpha-selectivity (alpha/beta ratio up to 9:1).
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Affiliation(s)
- Jiang-Lin Liang
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China
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Environmentally friendly TPDS-mediated free radical ring expansion of α-haloalkyl cyclic β-keto esters. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00241-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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