1
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Wang B, Zhang GM, Zhang H, Wang JY. B(C 6F 5) 3-catalyzed oxidation of α-diazoesters using DMF and molecular oxygen as oxygen sources. RSC Adv 2022; 12:33584-33588. [PMID: 36505720 PMCID: PMC9682326 DOI: 10.1039/d2ra05739e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 11/09/2022] [Indexed: 11/24/2022] Open
Abstract
A metal-free catalytic oxidation of α-diazoesters via a green environmental-friendly route was developed. The α-diazoesters were converted to α-ketoesters using DMF and molecular oxygen as oxygen sources and B(C6F5)3 as the catalyst, without any additives. This protocol has a broad adaptability of substrates and good compatibility with a range of functional groups, and it offers new insight into reactions catalyzed by B(C6F5)3.
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Affiliation(s)
- Bei Wang
- Department of Chemistry, Asymmetric Synthesis and Chiral Technology Key Laboratory of Sichuan Province, Xihua UniversityChengdu 610041P. R. China,Chengdu Institute of Organic Chemistry, Chinese Academy of SciencesChengdu 610041P. R. China,University of Chinese Academy of SciencesBeijing 100049P. R. China
| | - Guo-Min Zhang
- Department of Chemistry, Asymmetric Synthesis and Chiral Technology Key Laboratory of Sichuan Province, Xihua UniversityChengdu 610041P. R. China,Chengdu Institute of Organic Chemistry, Chinese Academy of SciencesChengdu 610041P. R. China,University of Chinese Academy of SciencesBeijing 100049P. R. China
| | - Hua Zhang
- Department of Chemistry, Asymmetric Synthesis and Chiral Technology Key Laboratory of Sichuan Province, Xihua UniversityChengdu 610041P. R. China,Chengdu Institute of Organic Chemistry, Chinese Academy of SciencesChengdu 610041P. R. China,University of Chinese Academy of SciencesBeijing 100049P. R. China
| | - Ji-Yu Wang
- Department of Chemistry, Asymmetric Synthesis and Chiral Technology Key Laboratory of Sichuan Province, Xihua UniversityChengdu 610041P. R. China,Chengdu Institute of Organic Chemistry, Chinese Academy of SciencesChengdu 610041P. R. China
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2
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Rhodium-Catalyzed Aerobic Conversion of 2-Diazo-1,3-dicarbonyls to Vicinal Tricarbonyl Compounds and Their In-Situ Stability Toward Oxidative Degradation. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.134521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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3
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Zhao S, Gao N, Bao N, Qian M, Chen ZY, Zhang MJ, Chen X. Stereoselective Synthesis of Tetrasubstituted Olefins via Visible-Light-Promoted Iodine-Mediated Homo-Coupling of Diazo. J Org Chem 2022; 87:11826-11837. [PMID: 36001822 DOI: 10.1021/acs.joc.2c01647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A visible-light-promoted iodine-mediated homo-coupling of diazo was first described. A series of tetrasubstituted olefins were synthesized in high yields and with low to high Z-selectivities from phenyldiazoacetates. For 3-diazooxindoles, isoindigo derivatives were provided in moderate to high yields and with excellent E-selectivities. Experimental results showed that the reaction proceeded through a diiodo intermediate. The synthetic usefulness of this reaction was illustrated by the synthesis of maleimide derivatives and dispiro epoxy.
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Affiliation(s)
- Shuai Zhao
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Nan Gao
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Ning Bao
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Mingcheng Qian
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Zi-Yun Chen
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Meng-Jia Zhang
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Xin Chen
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
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4
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Kaieda Y, Yamamoto K, Kuriyama M, Onomura O. Rhodium‐Catalyzed Transannulation of <i>N</i>‐Sulfonyl‐1,2,3‐triazoles with Carboxylic Esters. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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5
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Ruan M, Chen L, Wen Z, Yang F, Ma C, Lu C, Yang G, Gao M. Electrochemical two-electron oxygen reduction reaction (ORR) induced aerobic oxidation of α-diazoesters. Chem Commun (Camb) 2022; 58:2168-2171. [PMID: 35060985 DOI: 10.1039/d1cc06945d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Electrochemical oxygen reduction reaction (ORR) is a powerful tool for introducing oxygen functional groups in synthetic chemistry. However, compared with the well-developed one-electron oxygen reduction process, the applications of two-electron oxygen reduction in electrochemical synthesis have been seldom studied. We present herein our recent progress in the oxidation of α-diazoesters to α-ketoesters by in situ generated hydrogen peroxide via a two-electron oxygen reduction approach. A diverse collection of valuable α-ketoester products was obtained with moderate to high yields under an exogenous-oxidant-free and metal catalyst-free electrochemical conditions.
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Affiliation(s)
- Mengyao Ruan
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Liang Chen
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Ziyang Wen
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Fan Yang
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Chao Ma
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Cuifen Lu
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Guichun Yang
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
| | - Meng Gao
- Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, College of Chemistry and Chemical Engineering, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan, 430062, P. R. China.
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6
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Lu W, Li W, Zhou Y, Xie Y, Chen W. Iridium(I)-catalyzed deoxgenation of fluoroalkylsulfoxides with dimethyl diazomalonate to access fluoroalkylthioethers. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.02.061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Wu X, Gao W, Zhou Y, Liu M, Wu H. Tris(pentafluorophenyl)borane‐Catalyzed Oxygen Insertion Reaction of
α
‐Diazoesters (α‐Diazoamides) with Dimethyl Sulfoxide. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202101336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Xiao‐Yang Wu
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou 325035 People's Republic of China
| | - Wen‐Xia Gao
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou 325035 People's Republic of China
| | - Yun‐Bing Zhou
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou 325035 People's Republic of China
| | - Miao‐Chang Liu
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou 325035 People's Republic of China
| | - Hua‐Yue Wu
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou 325035 People's Republic of China
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8
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Li A, Hu LP, Yang T, Yang Z, Liu Y, Li LJ, Tang KW, Zhou CS. Copper-catalyzed [4+1] cycloannulation of 2-aminochalcones with ethyl diazophenylacetates via ester rearrangement. NEW J CHEM 2022. [DOI: 10.1039/d1nj02424h] [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
Copper-catalyzed [4+1] cycloannulation of 2-aminochalcones with ethyl diazophenylacetates was developed, exhibiting a wide range of substrates and good tolerance of functional groups.
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Affiliation(s)
- An Li
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Li Ping Hu
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Tao Yang
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Zan Yang
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Yu Liu
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Li Jun Li
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Ke Wen Tang
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
| | - Cong Shan Zhou
- Province Key Laboratory for Fine Petrochemical Catalysis and Separation, College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, Hunan, 414000, P. R. China
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9
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Zhang XJ, Zhang J, Xu YN, Li YM, Chi M, Yan Y, Wu RX, Zhang HR, Zhu YP. Cascade Wolff Rearrangement/Acylation: A Metal-Free and Eco-Friendly Approach for 4-Hydroxy-pyrazolo[3,4- b]pyridin-6-ones and N-Pyrazole Amides Synthesis from 5-Aminopyrazoles and α-Diazoketones. J Org Chem 2021; 86:17471-17481. [PMID: 34797656 DOI: 10.1021/acs.joc.1c02165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A highly chemoselective cascade Wolff rearrangement/acylation reaction between 5-aminopyrazoles and diazo compounds has been developed. The protocol can facilitate the switchable synthesis of 4-hydroxy-pyrazolo[3,4-b]pyridin-6-ones and N-pyrazole amides with the merits of a broad substrate scope, high functional group compatibility, and green and sustainable performance manner. All reactions proceeded efficiently without any catalyst and additives (acid and base) and resulted in the release of benign N2, wherein diethyl carbonate served as a green benign solvent.
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Affiliation(s)
- Xiang-Jin Zhang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Jie Zhang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Yu-Ning Xu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Yi-Ming Li
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Man Chi
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Yu Yan
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Rui-Xue Wu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Hui-Ru Zhang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
| | - Yan-Ping Zhu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Shandong, Yantai 264005, P. R. China
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10
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Zhao R, Teng J, Wang Z, Dong W, Lin J, Chu C. Copper on charcoal: Cu 0 nanoparticle catalysed aerobic oxidation of α-diazo esters. Org Biomol Chem 2021; 19:6120-6126. [PMID: 34179916 DOI: 10.1039/d1ob00811k] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By using a charcoal supported nano Cu0 catalyst (Cu/C), a highly efficient oxidation of α-diazo esters to α-ketoesters with molecular oxygen as the sole oxidant has been developed. In the presence of the Cu/C catalyst, 2-aryl-α-diazo esters with both electron-donating and electron-withdrawing groups can be oxidized to the corresponding α-ketoesters efficiently. Furthermore, this Cu/C catalyst can catalyse the reaction of aryl α-diazo ester with water to form aryl ketoester, 2-aryl-2-hydroxyl acetate ester and 2-aryl acetate ester. In this case, water is split by α-diazo ester, and the diazo group is displaced by the oxygen or hydrogen atom in water. Mechanistic investigation showed that the reaction of α-diazo ester with oxygen proceeds through a radical pathway. In the presence of 2,2,6,6-tetramethyl piperidine nitrogen oxide, the reaction of α-diazo ester with oxygen is dramatically inhibited. Furthermore, the reaction of α-diazo ester with water is investigated by an isotopic tracer method, and GCMS detection showed that a disproportionation reaction occurred between α-diazo ester and water.
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Affiliation(s)
- Rong Zhao
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; Shanghai Key Laboratory of New Drug Design; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Jiangge Teng
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; Shanghai Key Laboratory of New Drug Design; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Zhiwei Wang
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; Shanghai Key Laboratory of New Drug Design; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Wenwen Dong
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; Shanghai Key Laboratory of New Drug Design; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Jia Lin
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; Shanghai Key Laboratory of New Drug Design; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Changhu Chu
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; Shanghai Key Laboratory of New Drug Design; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
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11
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Mailloux MJ, Fleming GS, Kumta SS, Beeler AB. Unified Synthesis of Azepines by Visible-Light-Mediated Dearomative Ring Expansion of Aromatic N-Ylides. Org Lett 2021; 23:525-529. [PMID: 33395312 DOI: 10.1021/acs.orglett.0c04050] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Herein, we report a unified approach to azepines by dearomative photochemical rearrangement of aromatic N-ylides. Deprotonation of quaternary aromatic salts with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or N,N,N',N'-tetramethylquanidine (TMG) under visible light irradiation provides mono- and polycyclic azepines in yields up to 98%. This ring-expansion presents a new mode of access to functionalized azepines from N-heteroarenes using two straightforward steps and simple starting materials.
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Affiliation(s)
- Matthew J Mailloux
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Gabrielle S Fleming
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Shruti S Kumta
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Aaron B Beeler
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
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12
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Liu R, Liu Q, Meng H, Ding H, Hao J, Ji Z, Yue H, Wei W. Metal-free visible-light-induced aerobic oxidation of α-diazoesters leading to α-ketoesters in air. Org Chem Front 2021. [DOI: 10.1039/d0qo01587c] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A metal-free and visible-light-induced strategy has been established for the construction of α-ketoesters via aerobic oxidation of α-diazoesters with dioxygen in air at room temperature.
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Affiliation(s)
- Ruisheng Liu
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
| | - Qishun Liu
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
| | - Haoran Meng
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
| | - Hongyu Ding
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
| | - Jindong Hao
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
| | - Zhongyin Ji
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
| | - Huilan Yue
- Qinghai Provincial Key Laboratory of Tibetan Medicine Research and Key Laboratory of Tibetan Medicine Research
- Northwest Institute of Plateau Biology
- Chinese Academy of Sciences
- Qinghai 810008
- China
| | - Wei Wei
- School of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
- China
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13
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Zhu JL, Tsai YT. Rhodium-Catalyzed Aerobic Decomposition of 1,3-Diaryl-2-diazo-1,3-diketones: Mechanistic Investigation and Application to the Synthesis of Benzils. J Org Chem 2021; 86:813-828. [PMID: 33395740 DOI: 10.1021/acs.joc.0c02366] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The conversion of 1,3-diaryl-2-diazo-1,3-diketones to 1,2-daryl-1,2-diketones (benzils) is reported based on a rhodium(II)-catalyzed aerobic decomposition process. The reaction occurs at ambient temperatures and can be catalyzed by a few dirhodium carboxylates (5 mol %) under a balloon pressure of oxygen. Moreover, an oxygen atom from the O2 reagent is shown to be incorporated into the product, and this is accompanied by the extrusion of a carbonyl unit from the starting materials. Mechanistically, it is proposed that the decomposition may proceed via the interaction of a ketene intermediate resulting from a Wolff rearrangement of the carbenoid, with a rhodium peroxide or peroxy radical species generated upon the activation of molecular oxygen. The proposed mechanism has been supported by the results from a set of controlled experiments. By using this newly developed strategy, a large array of benzil derivatives as well as 9,10-phenanthrenequinone were synthesized from the corresponding diazo substrates in varying yields. On the other hand, the method did not allow the generation of benzocyclobutene-1,2-dione from 2-diazo-1,3-indandione because of the difficulty of inducing the initial rearrangement.
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Affiliation(s)
- Jia-Liang Zhu
- Department of Chemistry, National Dong Hwa University, No. 1, Sec. 2, Da Hsueh Rd., Shoufeng, Hualien 97401, Taiwan, ROC
| | - Yi-Ting Tsai
- Department of Chemistry, National Dong Hwa University, No. 1, Sec. 2, Da Hsueh Rd., Shoufeng, Hualien 97401, Taiwan, ROC
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