1
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Sonawane SC, Sabharwal G, Balakrishna MS. Cu I-Amidobis(phosphine)-Catalyzed Direct Amidation of Unactivated Alkanes via C(sp 3)-H Activation. Org Lett 2024. [PMID: 38804572 DOI: 10.1021/acs.orglett.4c01063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Herein, we describe an acid-base-free, sustainable, and efficient method for direct amidation of unactivated alkanes and toluene derivatives, using the dimeric CuI complex [CuI{o-Ph2PC6H4CONC6H4PPh2-o}2] (here onward referred to as [PNP-Cu]2). Using this method, C(sp3)-N bond formation was achieved through the activation of very challenging C(sp3)-H bonds in cycloalkanes, alkenes, allyl groups, and benzyl groups, with tolerance toward ketonic groups, heterocycles, and halide functionalities. One of the precatalysts, (PNHP-Cu-Npht) was isolated and structurally characterized. Isomerization in allyl-functionalized alkanes and selective benzylic alkylation in ketones were observed. This is a novel method for C(sp3)-N bond formation via direct N-alkylation of phthalimide, sulfonamide, benzamide, and phosphamidate.
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Affiliation(s)
- Sachin C Sonawane
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Gazal Sabharwal
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Maravanji S Balakrishna
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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2
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Liu R, Wang J, Wu H, Quan X, Wang S, Guo J, Wang Y, Li H. Stereocontrol in an intermolecular Schmidt reaction of equilibrating hydroxyalkyl allylic azides. Chem Commun (Camb) 2024; 60:4362-4365. [PMID: 38563154 DOI: 10.1039/d4cc00907j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
A selective intermolecular Schmidt reaction of equilibrating hydroxyalkyl allylic azides is reported to afford N-hydroxyalk-1-en-3-yl lactams in modest to high yields. For prochiral and chiral ketones, modest to high 1,5-diastereoselectivity was achieved, and the mechanistic analysis is supported by DFT calculation.
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Affiliation(s)
- Ruzhang Liu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Juan Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Hao Wu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Xianfeng Quan
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Shilin Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Jiandong Guo
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Yang Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Heting Li
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
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3
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Liu L, Jiang M, Zhang Q, Chen H, Zhang Y, Zhang J. Asymmetric total synthesis strategies of halichlorine and pinnaic acid. RSC Adv 2023; 13:33754-33769. [PMID: 38019985 PMCID: PMC10654894 DOI: 10.1039/d3ra06955a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 11/09/2023] [Indexed: 12/01/2023] Open
Abstract
Halichlorine and pinnaic acid are structurally related natural alkaloids isolated from different marine organisms. These two marine alkaloids bearing a 6-azaspiro[4.5]decane skeleton demonstrate a wide range of biological effects. It is this kind of unique structure and potentially valuable biological activity that have prompted strong synthetic interest, making it a research focus in recent years. Since the first total synthesis of halichlorine and pinnaic acid completed by Danishefsky's group, many groups have reported their outstanding synthesis methods especially the asymmetric synthesis strategies. This review summarizes the asymmetric synthesis strategies of halichlorine and pinnaic acid using a 6-azaspiro[4.5]decane skeleton as the key intermediate, which can provide some guidance for related work.
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Affiliation(s)
- Lu Liu
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Minghua Jiang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Qingkang Zhang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Hong Chen
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Yifu Zhang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
- Northwest Collaborative Innovation Center for Traditional Chinese Medicine Co-Constructed by Gansu Province & MOE of PRC Lanzhou 730000 P. R. China
| | - Jian Zhang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
- Northwest Collaborative Innovation Center for Traditional Chinese Medicine Co-Constructed by Gansu Province & MOE of PRC Lanzhou 730000 P. R. China
- Key Laboratory of Chemistry and Quality for TCM of the College of Gansu Province Lanzhou 730000 P. R. China
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4
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Isbel SR, Bugarin A. Synthesis of a New α-Azidomethyl Styrene from Safrole via a Dearomative Rearrangement. MOLBANK 2023; 2023:M1713. [PMID: 37920849 PMCID: PMC10621569 DOI: 10.3390/m1713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2023] Open
Abstract
There is a growing interest in developing more efficient synthetic alternatives for the synthesis of nitrogen-containing allylic compounds. This article presents a straightforward two-step protocol to produce 5-(3-azidoprop-1-en-2-yl)benzo[d][1,3]dioxole 4 from the natural product safrole. The method yielded the expected α-azidomethyl styrene 4, in good yield, via a dearomative rearrangement.
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Affiliation(s)
- Stephen R. Isbel
- Department of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, FL 33965, USA
| | - Alejandro Bugarin
- Department of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, FL 33965, USA
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5
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Kosteczka GL, Soek RN, Richter WE, Campos RB. Substituent effects on intramolecular Schmidt reactions: a theoretical study on the formation of bridged lactams. Org Biomol Chem 2023; 21:4114-4122. [PMID: 37129005 DOI: 10.1039/d3ob00532a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The competitive formation of isomeric bridged lactams via acid-catalyzed intramolecular Schmidt reactions from 3-azidoethylcyclopentanones is explored using density functional theory (DFT) calculations, primarily performed at the M06-2X/6-311++G(d,p) level of theory. The results indicate that specific substituents installed at α-carbons can efficiently control the regioselectivity of the reaction by lone pair-cation interactions or steric hindrance reversing the main product preference, whereas cation-π interactions are not so effective.
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Affiliation(s)
- Guilherme L Kosteczka
- Universidade Tecnológica Federal do Paraná, Rua Deputado Heitor de Alencar Furtado, 5000, 81280-340, Curitiba, PR, Brazil.
| | - Rafael N Soek
- Universidade Tecnológica Federal do Paraná, Rua Deputado Heitor de Alencar Furtado, 5000, 81280-340, Curitiba, PR, Brazil.
| | - Wagner E Richter
- Universidade Tecnológica Federal do Paraná, Rua Deputado Heitor de Alencar Furtado, 5000, 81280-340, Curitiba, PR, Brazil.
| | - Renan B Campos
- Universidade Tecnológica Federal do Paraná, Rua Deputado Heitor de Alencar Furtado, 5000, 81280-340, Curitiba, PR, Brazil.
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6
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Liu R, Tian Y, Wang J, Wang Z, Li X, Zhao C, Yao R, Li S, Yuan L, Yang J, Shi D. Visible light-initiated radical 1,3-difunctionalization of β,γ-unsaturated ketones. SCIENCE ADVANCES 2022; 8:eabq8596. [PMID: 36490351 PMCID: PMC9733936 DOI: 10.1126/sciadv.abq8596] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 11/03/2022] [Indexed: 06/17/2023]
Abstract
Radical-mediated 1,2-difunctionalization of olefins is a well-established synthetic technique widely used in the rapid construction of structurally diverse molecular entities. However, radical-mediated 1,3-difunctionalization reactions are rare, and the substrates are generally limited to strained skeletons. Here, we report a practical approach for 1,3-difunctionalization of available β,γ-unsaturated ketones via a radical cascade process including visible light-irradiated radical addition, thermodynamic stability-driven 1,2-carbonyl migration from unactivated all-carbon quaternary center, and terminal C-radical varied transformations. Various highly functionalized alkyl skeletons with different valuable functional groups at positions 1 and 3 and the carbonyl group at position 2 have been synthesized through a radical chain pathway or Cu-catalyzed Ritter-type reaction. Moreover, this protocol provides a real case of diversity-oriented radical rearrangement for drug discovery. We identified a previously unknown chemotype of dual inhibitors for hypoxia-inducible factor (HIF) and WNT signaling pathways from products. These small-molecule inhibitors could suppress HIF and WNT signaling-dependent HCT116 cell growth in 2D and 3D culture systems.
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Affiliation(s)
- Ruihua Liu
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Yang Tian
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Jie Wang
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, Shandong, P. R. China
| | - Zemin Wang
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Xiangqian Li
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Chenyang Zhao
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, Shandong, P. R. China
| | - Ruoyu Yao
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Shuo Li
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Leifeng Yuan
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
| | - Jinbo Yang
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, Shandong, P. R. China
| | - Dayong Shi
- State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China
- Laboratory of Marine Drugs and Biological Products, Pilot National Laboratory for Marine Science and Technology, 168 Weihai Road, Qingdao 266237, Shandong, P. R. China
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7
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Liu J, Zhang J, Fan Y, Ding H, Liu T, Li S, Jiang M, Liu L. Construction of azaspirocyclic skeletons mediated by the carbonyl of the Weinreb amide: formal total synthesis of (±)-cephalotaxine. Org Biomol Chem 2022; 20:1879-1882. [PMID: 35166743 DOI: 10.1039/d1ob02304g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile Stevens rearrangement of the Weinreb amide and the subsequent key steps mediated by the carbonyl of the Weinreb amide led to the construction of azaspirocyclic skeletons of some typical alkaloids. And the formal total synthesis of (±)-cephalotaxine was completed via a shorter synthetic route by this efficient method. Further studies on the development and asymmetric synthesis application of this strategy are underway.
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Affiliation(s)
- Jianyin Liu
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
| | - Jian Zhang
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China. .,Key Laboratory of Chemistry and Quality for TCM of the College of Gansu Province, Lanzhou 730000, P. R. China
| | - Yuxue Fan
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
| | - Huili Ding
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
| | - Tianfu Liu
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
| | - Shanshan Li
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
| | - Minghua Jiang
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
| | - Lu Liu
- School of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, P. R. China.
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8
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Liu R, Zhang Y, Xu J. Selective hydroboration of equilibrating allylic azides. Chem Commun (Camb) 2021; 57:8913-8916. [PMID: 35225991 DOI: 10.1039/d1cc02520a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The iridium(I)-catalyzed hydroboration of equilibrating allylic azides is reported to provide only the anti-Markovnikov product of alk-1-ene isomers in good yields and with good functional group tolerance.
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Affiliation(s)
- Ruzhang Liu
- College of Chemistry & Chemical Engineering, Yangzhou University, 180 Siwangting Rd, Yangzhou 225002, China.
| | - Yuanyuan Zhang
- College of Chemistry & Chemical Engineering, Yangzhou University, 180 Siwangting Rd, Yangzhou 225002, China.
| | - Jun Xu
- College of Chemistry & Chemical Engineering, Yangzhou University, 180 Siwangting Rd, Yangzhou 225002, China.
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9
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Forster D, Guo W, Wang Q, Zhu J. Photoredox Catalytic Three-Component Amidoazidation of 1,3-Dienes. ACS Catal 2021. [DOI: 10.1021/acscatal.1c03545] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Dan Forster
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland
| | - Weisi Guo
- College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, 53 Zhengzhou Road, Qingdao 266042, P. R. China
| | - Qian Wang
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland
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10
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Chatterjee B, Jena S, Chugh V, Weyhermüller T, Werlé C. A Molecular Iron-Based System for Divergent Bond Activation: Controlling the Reactivity of Aldehydes. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00733] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Basujit Chatterjee
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - Soumyashree Jena
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - Vishal Chugh
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
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11
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Bauer L, Benz M, Klapötke TM, Lenz T, Stierstorfer J. Polyazido-methyl Derivatives of Prominent Oxadiazole and Isoxazole Scaffolds: Synthesis, Explosive Properties, and Evaluation. J Org Chem 2021; 86:6371-6380. [DOI: 10.1021/acs.joc.1c00216] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Lukas Bauer
- Department of Chemistry, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13(D), D-81377 Munich, Germany
| | - Maximilian Benz
- Department of Chemistry, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13(D), D-81377 Munich, Germany
| | - Thomas M. Klapötke
- Department of Chemistry, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13(D), D-81377 Munich, Germany
| | - Tobias Lenz
- Department of Chemistry, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13(D), D-81377 Munich, Germany
| | - Jörg Stierstorfer
- Department of Chemistry, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13(D), D-81377 Munich, Germany
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12
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Gnägi L, Arnold R, Giornal F, Jangra H, Kapat A, Nyfeler E, Schärer RM, Zipse H, Renaud P. Stereoselective and Stereospecific Triflate-Mediated Intramolecular Schmidt Reaction: Ready Access to Alkaloid Skeletons*. Angew Chem Int Ed Engl 2021; 60:10179-10185. [PMID: 33594703 PMCID: PMC8251548 DOI: 10.1002/anie.202016892] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 02/11/2021] [Indexed: 11/10/2022]
Abstract
The stereoselectivity and stereospecificity of the triflate-mediated intramolecular Schmidt reaction of substituted 3-(1-azidocyclohexyl)propanol derivatives leading to octahydro-1H-pyrrolo[1,2-a]azepine, the structural skeleton of several important families of alkaloids such as the Stemona alkaloids, has been examined. The reaction involves an initial intramolecular SN 2 reaction between the azide moiety and the triflate affording an intermediate spirocyclic aminodiazonoium salt that undergoes the expected 1,2-shift/N2 -elimination followed by hydride-mediated iminium salt reduction. Remarkably, chiral alcohols are converted to the azabicyclic derivative with no or limited racemization. The initial asymmetric alcohol center controls the diastereoselectivity of the whole process, leading to the formation of one out of the four possible diastereoisomers of disubstituted octahydro-1H-pyrrolo[1,2-a]azepine. The origin of the stereoselectivity is rationalized based on theoretical calculations. The concise synthesis of (-)-(cis)-3-propylindolizidine and (-)-(cis)-3-butyllehmizidine, two alkaloids found in the venom of workers of the ant Myrmicaria melanogaster, is reported.
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Affiliation(s)
- Lars Gnägi
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Remo Arnold
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Florence Giornal
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Harish Jangra
- Department of Chemistry, LMU München, Butenandtstrasse 5-13, 81377, München, Germany
| | - Ajoy Kapat
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Erich Nyfeler
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Robin M Schärer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Hendrik Zipse
- Department of Chemistry, LMU München, Butenandtstrasse 5-13, 81377, München, Germany
| | - Philippe Renaud
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
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13
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Gnägi L, Arnold R, Giornal F, Jangra H, Kapat A, Nyfeler E, Schärer RM, Zipse H, Renaud P. Stereoselective and Stereospecific Triflate‐Mediated Intramolecular Schmidt Reaction: Ready Access to Alkaloid Skeletons**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016892] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Lars Gnägi
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
| | - Remo Arnold
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
| | - Florence Giornal
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
| | - Harish Jangra
- Department of Chemistry LMU München Butenandtstrasse 5–13 81377 München Germany
| | - Ajoy Kapat
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
| | - Erich Nyfeler
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
| | - Robin M. Schärer
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
| | - Hendrik Zipse
- Department of Chemistry LMU München Butenandtstrasse 5–13 81377 München Germany
| | - Philippe Renaud
- Department of Chemistry and Biochemistry University of Bern Freiestrasse 3 3012 Bern Switzerland
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14
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Liu R, Wei Z, Wang J, Liu Y, Xue H. Highly selective hydrosilylation of equilibrating allylic azides. Chem Commun (Camb) 2020; 56:5038-5041. [PMID: 32242569 DOI: 10.1039/d0cc01316a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The Pt-catalyzed hydrosilylation of equilibrating allylic azides is reported. The reaction provides only one out of four possible hydrosilylation products in good yields and with very high chemoselectivity (alk-1-ene vs. alk-2-ene), regioselectivity (linear vs. branched), and excellent functional group tolerance.
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Affiliation(s)
- Ruzhang Liu
- College of Chemistry & Chemical Engineering, Yangzhou University, 180 Siwangting Rd., Yangzhou 225002, China.
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15
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Tjeng AA, Handore KL, Batey RA. Stereocontrolled Microwave-Assisted Domino [3,3]-Sigmatropic Reactions: A Winstein-Overman Rearrangement for the Formation of Differentiated Contiguous C-N Bonds. Org Lett 2020; 22:3050-3055. [PMID: 32223252 DOI: 10.1021/acs.orglett.0c00801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A domino [3,3]-sigmatropic rearrangement sequence employing a sequential reversible allylic azide rearrangement followed by an irreversible Overman reaction provides a new route to the formation of two contiguous C-N bonds. The reaction occurs in a stereocontrolled fashion in two steps from readily available alkenyl epoxides via initial azide anion ring opening of the epoxides.
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Affiliation(s)
- Andy A Tjeng
- Davenport Research Laboratories, Dept. of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
| | - Kishor L Handore
- Davenport Research Laboratories, Dept. of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
| | - Robert A Batey
- Davenport Research Laboratories, Dept. of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
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16
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Wen X, Li X, Luo X, Wang W, Song S, Jiao N. Intramolecular Csp 3-H/C-C bond amination of alkyl azides for the selective synthesis of cyclic imines and tertiary amines. Chem Sci 2020; 11:4482-4487. [PMID: 34122906 PMCID: PMC8159442 DOI: 10.1039/c9sc05522c] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The intramolecular Csp3–H and/or C–C bond amination is very important in modern organic synthesis due to its efficiency in the construction of diversified N-heterocycles. Herein, we report a novel intramolecular cyclization of alkyl azides for the synthesis of cyclic imines and tertiary amines through selective Csp3–H and/or C–C bond cleavage. Two C–N single bonds or a C
Created by potrace 1.16, written by Peter Selinger 2001-2019
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N double bond are efficiently constructed in these transformations. The carbocation mechanism differs from the reported metal nitrene intermediates and therefore enables metal-free and new transformation. A novel intramolecular cyclization of alkyl azides for the synthesis of cyclic imines and tertiary amines has been developed. The aliphatic C–H or C–C bond was selectively cleaved with the efficient formation of two C–N single bonds or a CN double bond.![]()
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Affiliation(s)
- Xiaojin Wen
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Xinyao Li
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Xiao Luo
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Weijin Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Song Song
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China .,State Key Laboratory of Drug Research, Shanghai Institute of Materia Medical, Chinese Academy of Sciences Shanghai 201203 China
| | - Ning Jiao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
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18
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Vallejos MM, Labadie GR. Insight into the factors controlling the equilibrium of allylic azides. RSC Adv 2020; 10:4404-4413. [PMID: 35495248 PMCID: PMC9049130 DOI: 10.1039/c9ra10093h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 12/26/2019] [Indexed: 12/19/2022] Open
Abstract
Several allylic azides with different double bond substitutions were studied to understand the factors, governing their equilibrium using density functional theory along with the quantum theory of atoms in molecules, non-covalent interactions and natural bond orbital approaches. The results showed that the hydroxyl group or heteroatoms in allylic azides interact with the molecule through an electrostatic weak interaction in each pair of regioisomers. The equilibrium shifts of substituted allylic azides, compared to non-substituted allylic azides, were not attributed to the presence of specific interactions, such as hydrogen bonds. The observed equilibrium shifts stemmed mainly from the strengthening and weakening of negative hyperconjugative interactions, which were affected by the weak interaction involving the proximal substituent in each regioisomer. A good linear correlation was obtained between the hyperconjugative energies of πC
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C→σ*Zb interactions and the calculated percentages of the secondary azide and tertiary azide in the equilibrium mixture. Also, the effect of the aromatic ring substituent was analysed using such approaches. This study not only provides insights into the factors controlling the stabilities of the substituted allylic azides, but also settles the basis to predict the regioisomer predominance in the equilibrium mixture. The factors controlling the allyl azides equilibrium has been studied by different theoretical approaches setting the basis to predict the regioisomers predominance in the equilibrium mixture.![]()
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Affiliation(s)
- Margarita M Vallejos
- Laboratorio de Química Orgánica, IQUIBA-NEA, Universidad Nacional del Nordeste, CONICET, FACENA Av. Libertad 5460 Corrientes 3400 Argentina +54-379-4457996 ext. 104
| | - Guillermo R Labadie
- Instituto de Química Rosario, UNR, CONICET Suipacha 531 S2002LRK Rosario Argentina.,Departamento de Química Orgánica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario Suipacha 531 S2002LRK Rosario Argentina
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19
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Liu Y, Ding N, Tan X, Li X, Zhao Z. Iron(ii)-chloride-catalyzed regioselective azidation of allenamides with TMSN3. Chem Commun (Camb) 2020; 56:7507-7510. [DOI: 10.1039/c9cc10056c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The first report of iron catalyzed azidation of allenamides via radical process to provide an efficient route for accessing allyl azides.
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Affiliation(s)
- Yongchun Liu
- College of Chemistry and Environmental Protection Engineering
- Southwest Minzu University
- Chengdu 610041
- People's Republic of China
| | - Na Ding
- College of Chemistry and Environmental Protection Engineering
- Southwest Minzu University
- Chengdu 610041
- People's Republic of China
| | - Xiaoju Tan
- College of Chemistry and Environmental Protection Engineering
- Southwest Minzu University
- Chengdu 610041
- People's Republic of China
| | - Xiaoxiao Li
- College of Chemistry and Environmental Protection Engineering
- Southwest Minzu University
- Chengdu 610041
- People's Republic of China
| | - Zhigang Zhao
- College of Chemistry and Environmental Protection Engineering
- Southwest Minzu University
- Chengdu 610041
- People's Republic of China
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Abstract
Allylic azides are underutilized in organic synthesis when compared to other organic azides or other allylic functionality. This is likely because allylic azides rearrange at room temperature, resulting in a potentially complex mixture of azides. This rearrangement has been termed the Winstein rearrangement. Understanding the mechanism and basic principles governing the allylic azide equilibrium may aid in developing applications for these molecules based on either alkene or azide functionalization. Presented herein is a compilation of the key observations regarding the nature of the allylic azide rearrangement. Mechanistic considerations are explicitly addressed with key examples from the literature.
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Affiliation(s)
- Amy A Ott
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Joseph J Topczewski
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
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21
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Carlson AS, Topczewski JJ. Allylic azides: synthesis, reactivity, and the Winstein rearrangement. Org Biomol Chem 2019; 17:4406-4429. [PMID: 30969292 PMCID: PMC6530792 DOI: 10.1039/c8ob03178a] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Organic azides are useful synthetic intermediates, which demonstrate broad reactivity. Unlike most organic azides, allylic azides can spontaneously rearrange to form a mixture of isomers. This rearrangement has been named the Winstein rearrangement. Using allylic azides can result in low yields and azide racemization in some synthetic contexts due to the Winstein rearrangement. Effort has been made to understand the mechanism of the Winstein rearrangement and to take advantage of this process. Several guiding principles can be used to identify which azides will produce a mixture of isomers and which will resist rearrangement. Selective reaction conditions can be used to differentiate the azide isomers in a dynamic manner. This review covers all aspects of allylic azides including their synthesis, their reactivity, the mechanism of the Winstein rearrangement, and reactions that can selectively elaborate an azide isomer. This review covers the literature from Winstein's initial report to early 2019.
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Affiliation(s)
- Angela S Carlson
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
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22
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Automatic mapping of atoms across both simple and complex chemical reactions. Nat Commun 2019; 10:1434. [PMID: 30926819 PMCID: PMC6441094 DOI: 10.1038/s41467-019-09440-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 03/01/2019] [Indexed: 11/08/2022] Open
Abstract
Mapping atoms across chemical reactions is important for substructure searches, automatic extraction of reaction rules, identification of metabolic pathways, and more. Unfortunately, the existing mapping algorithms can deal adequately only with relatively simple reactions but not those in which expert chemists would benefit from computer's help. Here we report how a combination of algorithmics and expert chemical knowledge significantly improves the performance of atom mapping, allowing the machine to deal with even the most mechanistically complex chemical and biochemical transformations. The key feature of our approach is the use of few but judiciously chosen reaction templates that are used to generate plausible "intermediate" atom assignments which then guide a graph-theoretical algorithm towards the chemically correct isomorphic mappings. The algorithm performs significantly better than the available state-of-the-art reaction mappers, suggesting its uses in database curation, mechanism assignments, and - above all - machine extraction of reaction rules underlying modern synthesis-planning programs.
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23
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Liu EC, Topczewski JJ. Enantioselective Copper Catalyzed Alkyne-Azide Cycloaddition by Dynamic Kinetic Resolution. J Am Chem Soc 2019; 141:5135-5138. [PMID: 30888164 DOI: 10.1021/jacs.9b01091] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The copper(I) catalyzed alkyne-azide cycloaddition (CuAAC), a click reaction, is one of the most powerful catalytic reactions developed during the last two decades. Conducting CuAAC enantioselectively would add a third dimension to this reaction and would enable the direct synthesis of α-chiral triazoles. Doing so is demanding because the two precursors have linear geometries, and the triazole product is a flat heterocycle. Designing a chiral catalyst is further complicated by the complex mechanism of CuAAC. We report an enantioselective CuAAC (E-CuAAC), enabled by dynamic kinetic resolution (DKR). The E-CuAAC is high yielding and affords up to 99:1 er. The E-CuAAC can directly generate α-chiral triazoles in a complex molecular environment.
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Affiliation(s)
- En-Chih Liu
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis Minnesota 55455 , United States
| | - Joseph J Topczewski
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis Minnesota 55455 , United States
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24
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Ojo OS, Miranda O, Baumgardner KC, Bugarin A. Practical regio- and stereoselective azidation and amination of terminal alkenes. Org Biomol Chem 2019; 16:9354-9358. [PMID: 30489592 DOI: 10.1039/c8ob02734j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
There is significant interest in developing more rapid and efficient production of nitrogen-containing allylic compounds, as widely used in various syntheses. This work reports a variety of allylic azides and allylic amines synthesized by an efficient, new one-pot protocol that employs readily available terminal alkenes as starting materials. This method is highly regio- and stereoselective, affording the linear (E)-isomer, under metal-free conditions. This process tolerates several functional groups including halogen-containing molecules; it is general for azides and amine nucleophiles; and, adducts were obtained in good yields.
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Affiliation(s)
- Olatunji S Ojo
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX 76019, USA.
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25
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Piątek A, Chapuis C. Diels-Alder Reaction of Cyclopenta-1,3-diene and Anthracene to bis-Fumarates Derived from Menthol Analogues. ChemistrySelect 2019. [DOI: 10.1002/slct.201803003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Anna Piątek
- Department of Chemistry; University of Warsaw; Pasteura 1 PL-02-093 Warsaw
| | - Christian Chapuis
- Institute of Organic Chemistry; Polish Academy of Sciences; Kasprzaka 44/52 PL-01-224 Warsaw Poland
- Firmenich SA; Corporate R&D Division; P.O.Box 239 CH-1211 Geneva 8
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Abstract
The first detailed description of the catalytic racemization of activated benzylic and allylic azides under mild conditions is reported. A kinetic analysis of the observed racemization indicates a first-order dependence on azide, a first-order dependence on catalyst, and that the rate of racemization correlates to σ+. A variety of azides with varying substitution patterns undergo facile racemization, and catalyst selection can tune this process.
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Affiliation(s)
- Amy A Ott
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Joseph J Topczewski
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
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27
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Topczewski JJ, Porter MR. "It's a (Kinetic) Trap!" - Selectively Differentiating Allylic Azide Isomers. Synlett 2018; 29:1537-1542. [PMID: 30505072 PMCID: PMC6258082 DOI: 10.1055/s-0037-1609479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Allylic azides are known to undergo the Winstein rearrangement and are often isolated as an equilibrating mixture of isomers. While this process has been known for almost 60 years, very few synthetic applications of this process have been reported. The absence of methods exploiting these intermediates likely stems from a paucity of approaches for gaining the required selectivity to differentiate the isomers. Our lab has made some progress in leveraging this unusual reaction into practical synthetic methodology. Presented herein is a summary of our lab's recent accomplishments in selectively trapping allylic azides.
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Affiliation(s)
- Joseph J Topczewski
- Department of Chemistry, University of Minnesota - Twin Cities, 207 Pleasant St. SE, Minneapolis MN 55455, USA
| | - Matthew R Porter
- Department of Chemistry, University of Minnesota - Twin Cities, 207 Pleasant St. SE, Minneapolis MN 55455, USA
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Ott AA, Packard MH, Ortuño MA, Johnson A, Suding VP, Cramer CJ, Topczewski JJ. Evidence for a Sigmatropic and an Ionic Pathway in the Winstein Rearrangement. J Org Chem 2018; 83:8214-8224. [PMID: 29870252 DOI: 10.1021/acs.joc.8b00961] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The spontaneous rearrangement of allylic azides is thought to be a sigmatropic reaction. Presented herein is a detailed investigation into the rearrangement of several allylic azides. A combination of experiments including equilibrium studies, kinetic analysis, density functional theory calculations, and selective 15N-isotopic labeling are included. We conclude that the Winstein rearrangement occurs by the assumed sigmatropic pathway under most conditions. However, racemization was observed for some cyclic allylic azides. A kinetic analysis of this process is provided, which supports a previously undescribed ionic pathway.
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Affiliation(s)
- Amy A Ott
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Mary H Packard
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Manuel A Ortuño
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Alayna Johnson
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Victoria P Suding
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Christopher J Cramer
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
| | - Joseph J Topczewski
- Department of Chemistry , University of Minnesota Twin Cities , Minneapolis , Minnesota 55455 , United States
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29
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Walker MM, Chen S, Mercado BQ, Houk KN, Ellman JA. Formation of Aminocyclopentadienes from Silyldihydropyridines: Ring Contractions Driven by Anion Stabilization. Angew Chem Int Ed Engl 2018; 57:6605-6609. [PMID: 29570926 DOI: 10.1002/anie.201800596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/20/2018] [Indexed: 11/09/2022]
Abstract
Highly functionalized aminocyclopentadienes can be formed through the rearrangement of anions generated from readily prepared 6-silyl-1,2-dihydropyridines by desilylation with fluoride. The scope and generality of the reaction was defined, and diverse transformations were performed on the highly functionalized products. A mechanism and driving force for the rearrangement were identified from experiments and DFT calculations.
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Affiliation(s)
- Morgan M Walker
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT, 06520, USA
| | - Shuming Chen
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Brandon Q Mercado
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT, 06520, USA
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Jonathan A Ellman
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT, 06520, USA
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30
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Walker MM, Chen S, Mercado BQ, Houk KN, Ellman JA. Formation of Aminocyclopentadienes from Silyldihydropyridines: Ring Contractions Driven by Anion Stabilization. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201800596] [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]
Affiliation(s)
- Morgan M. Walker
- Department of Chemistry Yale University 225 Prospect St. New Haven CT 06520 USA
| | - Shuming Chen
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095-1569 USA
| | - Brandon Q. Mercado
- Department of Chemistry Yale University 225 Prospect St. New Haven CT 06520 USA
| | - K. N. Houk
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095-1569 USA
| | - Jonathan A. Ellman
- Department of Chemistry Yale University 225 Prospect St. New Haven CT 06520 USA
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Zhao Y, Zhou Y, Zhang C, Li D, Sun P, Li J, Wang H, Liu J, Qu J. Base-Controlled Regiodivergent Azidation of Trifluoromethyl Alkenyl Triflates: Transition-Metal-Free Access to CF 3-Containing Allyl Azides and Alkenyl Azides. J Org Chem 2018; 83:2858-2868. [PMID: 29384677 DOI: 10.1021/acs.joc.7b03294] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A base-controlled regiodivergent azidation of trifluoromethyl alkenyl triflates providing either (E)-3-azido-1-aryl-4,4,4-trifluorobut-1-ene (CF3-containing allyl azides) or (Z)-1-azido-1-aryl-4,4,4-trifluorobut-1-ene (CF3-containing alkenyl azides) is described. Catalyzed by Et3N, the azidation of trifluoromethyl alkenyl triflates with TMSN3 gave CF3-containing allyl azides. On the other hand, using stoichiometric DBU, the regioisomeric azidation products, CF3-containing alkenyl azides, were obtained in good yield. A further transformation for CF3-containing amines, triazoles, and azirines highlights the practical applicability of this transition-metal-free protocol.
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Affiliation(s)
- Yilong Zhao
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Yuhan Zhou
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Chunxia Zhang
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Dong Li
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Puhua Sun
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Jianzhe Li
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Huan Wang
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
| | - Jianhui Liu
- School of Petroleum and Chemical Engineering, Dalian University of Technology , Panjin 124221, People's Republic of China
| | - Jingping Qu
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian 116024, People's Republic of China
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Shao J, Zhu M, Gao L, Chen H, Li X. Synthesis of tetracyclic azasugars fused benzo[ e ][1,3]thiazin-4-one by the tandem Staudinger/aza-Wittig/cyclization and their HIV-RT inhibitory activity. Carbohydr Res 2018; 456:45-52. [DOI: 10.1016/j.carres.2017.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/12/2017] [Accepted: 12/12/2017] [Indexed: 11/25/2022]
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Porter MR, Shaker RM, Calcanas C, Topczewski JJ. Stereoselective Dynamic Cyclization of Allylic Azides: Synthesis of Tetralins, Chromanes, and Tetrahydroquinolines. J Am Chem Soc 2018; 140:1211-1214. [PMID: 29303567 PMCID: PMC5989720 DOI: 10.1021/jacs.7b11299] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This report describes the stereoselective synthesis of 3-azido-tetralins, -chromanes, and -tetrahydroquinolines via a tandem allylic azide rearrangement/Friedel-Crafts alkylation. Exposure of allylic azides with a pendant trichloroacetimidate to catalytic quantities of AgSbF6 proved optimal for this transformation. This cascade successfully differentiates the equilibrating azide isomers, providing products in excellent yield and selectivity (>25 examples, up to 94% yield and >25:1 dr). In many cases, the reactive isomer is only a trace fraction of the equilibrium mixture, keenly illustrating the dynamic nature of these systems. We demonstrate the utility of this process via a synthesis of hasubanan.
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Affiliation(s)
- Matthew R. Porter
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Rami M. Shaker
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Cristian Calcanas
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Joseph J. Topczewski
- Department of Chemistry, University of Minnesota Twin Cities, Minneapolis, Minnesota 55455, United States
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Ding PG, Hu XS, Zhou F, Zhou J. Catalytic enantioselective synthesis of α-chiral azides. Org Chem Front 2018. [DOI: 10.1039/c8qo00138c] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The catalytic asymmetric synthesis of α-chiral azides is of current interest and three synthetic strategies have been developed. This review summarizes the recent progress in this research area, discusses the advantages and limitations of each strategy, and outlines synthetic opportunities for future research.
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Affiliation(s)
- Pei-Gang Ding
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- People's Republic of China
| | - Xiao-Si Hu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- People's Republic of China
| | - Feng Zhou
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- People's Republic of China
| | - Jian Zhou
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- People's Republic of China
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35
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Kang HY, Kang YK. Allylic Azide Rearrangements Investigated by Density Functional Theory Calculations. B KOREAN CHEM SOC 2017. [DOI: 10.1002/bkcs.11318] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Han-Young Kang
- Department of Chemistry; Chungbuk National University; Cheongju Chungbuk, 28644 Korea
| | - Young Kee Kang
- Department of Chemistry; Chungbuk National University; Cheongju Chungbuk, 28644 Korea
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36
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Packard MH, Cox JH, Suding VP, Topczewski JJ. The Effect of Proximal Functionality on the Allylic Azide Equilibrium. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700693] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Mary H. Packard
- Department of Chemistry; University of Minnesota; 55455 Minneapolis MN USA
| | - James H. Cox
- Department of Chemistry; University of Minnesota; 55455 Minneapolis MN USA
| | - Victoria P. Suding
- Department of Chemistry; University of Minnesota; 55455 Minneapolis MN USA
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37
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Ott AA, Goshey CS, Topczewski JJ. Dynamic Kinetic Resolution of Allylic Azides via Asymmetric Dihydroxylation. J Am Chem Soc 2017; 139:7737-7740. [PMID: 28574252 DOI: 10.1021/jacs.7b04203] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The catalytic enantioselective preparation of densely functionalized amines is a fundamental synthetic challenge. To address this challenge, we report for the first time that the Winstein rearrangement can be enlisted as the racemization pathway in a dynamic kinetic resolution of allylic azides. Alkene functionalization by Sharpless dihydroxylation affords tertiary azides in excellent enantioselectivity (up to 99:1 er). This approach establishes the chirality of the tertiary azide, obviates the need to directly forge either a congested C-N or C-C bond at the new nitrogenous stereocenter, and establishes additional functionality. Several examples demonstrate further elaboration of this functionality.
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Affiliation(s)
- Amy A Ott
- Department of Chemistry, University of Minnesota Twin Cities , Minneapolis, Minnesota 55455, United States
| | - Charles S Goshey
- Department of Chemistry, University of Minnesota Twin Cities , Minneapolis, Minnesota 55455, United States
| | - Joseph J Topczewski
- Department of Chemistry, University of Minnesota Twin Cities , Minneapolis, Minnesota 55455, United States
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38
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López E, López LA. Synthesis of Functionalized Cyclopentene Derivatives from Vinyldiazo Compounds and Vinylazides through Sequential Copper-Promoted [3+2] Cycloaddition/Azide Rearrangement. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701572] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Enol López
- Departmento de Química Orgánica e Inorgánica and Instituto Universitario de Química Organometálica “Enrique Moles”; Universidad de Oviedo; Julián Clavería 8 33006- Oviedo Spain
| | - Luis A. López
- Departmento de Química Orgánica e Inorgánica and Instituto Universitario de Química Organometálica “Enrique Moles”; Universidad de Oviedo; Julián Clavería 8 33006- Oviedo Spain
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López E, López LA. Synthesis of Functionalized Cyclopentene Derivatives from Vinyldiazo Compounds and Vinylazides through Sequential Copper-Promoted [3+2] Cycloaddition/Azide Rearrangement. Angew Chem Int Ed Engl 2017; 56:5121-5124. [DOI: 10.1002/anie.201701572] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 03/07/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Enol López
- Departmento de Química Orgánica e Inorgánica and Instituto Universitario de Química Organometálica “Enrique Moles”; Universidad de Oviedo; Julián Clavería 8 33006- Oviedo Spain
| | - Luis A. López
- Departmento de Química Orgánica e Inorgánica and Instituto Universitario de Química Organometálica “Enrique Moles”; Universidad de Oviedo; Julián Clavería 8 33006- Oviedo Spain
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40
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Liu C, Szostak M. Twisted Amides: From Obscurity to Broadly Useful Transition-Metal-Catalyzed Reactions by N−C Amide Bond Activation. Chemistry 2017; 23:7157-7173. [DOI: 10.1002/chem.201605012] [Citation(s) in RCA: 246] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Chengwei Liu
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 USA
| | - Michal Szostak
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 USA
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41
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Curton N, Ornelas J, Uhrinak A, Rhem B, Coulter J, Zhang J, Joyner PM, White JB. Synthesis of 5-cyclodecenones via RCM and a three-pot sequence for bisannulation. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2016.07.084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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42
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Vale JR, Siopa F, Branco PS, Afonso CAM. Ring Opening of 6-Azabicyclo[3.1.0]hex-3-en-2-ols in Water under Mild Conditions. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501468] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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43
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Moynihan L, Chadda R, McArdle P, Murphy PV. Allylic Azide Rearrangement in Tandem with Huisgen Cycloaddition for Stereoselective Annulation: Synthesis of C-Glycosyl Iminosugars. Org Lett 2015; 17:6226-9. [PMID: 26650965 DOI: 10.1021/acs.orglett.5b03209] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Allylic azide rearrangement is used in tandem with intramolecular azide-alkene cycloaddition to give a triazoline that when subsequently decomposed in the presence of a nucleophile gives piperidines. The tandem reaction gives two stereocenters that are generated with high control. The formation of the piperidines required the presence of innate conformational constraint. The applicability of the annulation reaction is demonstrated by the synthesis of iminosugars. A proposal is included to account for the observed stereoselectivity, which is influenced by the precursor structure.
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Affiliation(s)
- Lorna Moynihan
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland
| | - Rekha Chadda
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland
| | - Patrick McArdle
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland
| | - Paul V Murphy
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland
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44
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Frankowski KJ, Liu R, Milligan GL, Moeller KD, Aubé J. Practical Electrochemical Anodic Oxidation of Polycyclic Lactams for Late Stage Functionalization. Angew Chem Int Ed Engl 2015; 54:10555-8. [PMID: 26371961 PMCID: PMC4629799 DOI: 10.1002/anie.201504775] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 06/12/2015] [Indexed: 01/01/2023]
Abstract
Electrochemistry provides a powerful tool for the late-stage functionalization of complex lactams. A two-stage protocol for converting lactams, many of which can be prepared through the intramolecular Schmidt reaction of keto azides, is presented. In the first step, anodic oxidation in MeOH using a repurposed power source provides a convenient route to lactams bearing a methoxy group adjacent to nitrogen. Treatment of these intermediates with a Lewis acid in dichloromethane permits the regeneration of a reactive acyliminium ion that is then reacted with a range of nucleophilic species.
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Affiliation(s)
- Kevin J Frankowski
- Department of Medicinal Chemistry, University of Kansas, 2034 Becker Drive, Lawrence, KS 66047 (USA)
- Present address: Division of Chemical Biology and Medicinal Chemistry and the Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, University of North Carolina, North Carolina, 27599, USA
| | - Ruzhang Liu
- Department of Medicinal Chemistry, University of Kansas, 2034 Becker Drive, Lawrence, KS 66047 (USA)
| | - Gregory L Milligan
- Department of Chemistry, Saint Martin's University, 5000 Abbey Way, Lacey, WA 98503 (USA)
| | - Kevin D Moeller
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130 (USA)
| | - Jeffrey Aubé
- Department of Medicinal Chemistry, University of Kansas, 2034 Becker Drive, Lawrence, KS 66047 (USA).
- Present address: Division of Chemical Biology and Medicinal Chemistry and the Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, University of North Carolina, North Carolina, 27599, USA.
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45
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Frankowski KJ, Liu R, Milligan GL, Moeller KD, Aubé J. Practical Electrochemical Anodic Oxidation of Polycyclic Lactams for Late Stage Functionalization. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504775] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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46
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Shinde MV, Ople RS, Sangtani E, Gonnade R, Reddy DS. Synthesis of novel N-cyclopentenyl-lactams using the Aubé reaction. Beilstein J Org Chem 2015. [PMID: 26199661 PMCID: PMC4505090 DOI: 10.3762/bjoc.11.119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
A novel and convenient method utilizing the Aubé reaction to access a new class of compounds that are similar to carbocyclic nucleosides is reported. The azido alcohol derived from Vince lactam undergoes the Aubé reaction with various cyclic ketones to give cyclopentenyl-substituted lactams. Upon dihydroxylation, this affords the N-cyclopentenyl-lactam compounds in racemic form. Given the numerous uses of nucleosides and related compounds, we were interested in the synthesis of carbocylic nucleoside mimics. The attempts and results are described herein.
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Affiliation(s)
- Madhuri V Shinde
- Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
| | - Rohini S Ople
- Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
| | - Ekta Sangtani
- Center for Material Characterization, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
| | - Rajesh Gonnade
- Center for Material Characterization, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
| | - D Srinivasa Reddy
- Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
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47
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Thevenet N, de la Sovera V, Vila MA, Veiga N, Gonzalez D, Seoane G, Carrera I. Double [3,3]-Sigmatropic Rearrangement in the Enzymatic Dioxygenation of Benzyl Azide: Preparation of Novel Synthetically Valuable Azido-diols. Org Lett 2015; 17:684-7. [DOI: 10.1021/ol503708v] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Natalia Thevenet
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
| | - Victoria de la Sovera
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
| | - María Agustina Vila
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
| | - Nicolás Veiga
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
| | - David Gonzalez
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
| | - Gustavo Seoane
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
| | - Ignacio Carrera
- Departamento de Química
Orgánica and ‡Departamento Estrella Campos, Facultad de Química - Universidad de la República, General Flores 2124, CP 11800, Montevideo, Uruguay
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48
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Moskalenko AI, Boev VI. Intramolecular Schmidt reaction of tert-butyl 3-(3-azidopropyl)-4-oxopiperidine-1-carboxylate as a synthetic route to saturated fused aza heterocycles. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2014. [DOI: 10.1134/s1070428014090176] [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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49
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Vekariya RH, Liu R, Aubé J. A concomitant allylic azide rearrangement/intramolecular azide-alkyne cycloaddition sequence. Org Lett 2014; 16:1844-7. [PMID: 24635056 PMCID: PMC3993870 DOI: 10.1021/ol500011f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
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An intramolecular Huisgen cycloaddition
of an interconverting set
of isomeric allylic azides with alkynes affords substituted triazoles
in high yield. The stereoisomeric vinyl-substituted triazoloxazines
formed depend on the rate of cycloaddition of the different allylic
azide precursors when the reaction is carried out under thermal conditions.
In contrast, dimerized macrocyclic products were obtained when the
reaction was done using copper(I)-catalyzed conditions, demonstrating
the ability to control the reaction products through changing conditions.
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Affiliation(s)
- Rakesh H Vekariya
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
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50
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Ortiz GX, Kang B, Wang Q. One-Pot Synthesis of 3-Azido- and 3-Aminopiperidines by Intramolecular Cyclization of Unsaturated Amines. J Org Chem 2014; 79:571-81. [DOI: 10.1021/jo4022666] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Gerardo X. Ortiz
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Bora Kang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Qiu Wang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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