1
|
Yagci BB, Donmez SE, Şahin O, Türkmen YE. Catalytic aza-Nazarov cyclization reactions to access α-methylene-γ-lactam heterocycles. Beilstein J Org Chem 2023; 19:66-77. [PMID: 36741815 PMCID: PMC9874235 DOI: 10.3762/bjoc.19.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 01/10/2023] [Indexed: 01/19/2023] Open
Abstract
We have developed a catalytic aza-Nazarov reaction of N-acyliminium salts generated in situ from the reaction of a variety of cyclic and acyclic imines with α,β-unsaturated acyl chlorides to afford substituted α-methylene-γ-lactam heterocycles. The reactions proceed effectively in the presence of catalytic (20 mol %) amounts of AgOTf as an anion exchange agent or hydrogen-bond donors such as squaramides and thioureas as anion-binding organocatalysts. The aza-Nazarov cyclization of 3,4-dihydroisoquinolines with α,β-unsaturated acyl chlorides gives tricyclic lactam products 7 in up to 79% yield with full diastereocontrol (dr = >99:1). The use of acyclic imines in a similar catalytic aza-Nazarov reaction with 20 mol % of AgOTf results in the formation of α-methylene-γ-lactam heterocycles 19 in up to 76% yield and with good to high diastereoselectivities (4.3:1 to 16:1). We have demonstrated the scalability of the reaction with a gram-scale example. The relative stereochemistry of the α-methylene-γ-lactam products 19 has been determined via the single-crystal X-ray analysis of lactam 19l. In order to shed light on the details of the reaction mechanism, we have performed carefully designed mechanistic studies which consist of experiments on the effect of β-silicon stabilization, the alkene geometry of the α,β-unsaturated acyl chloride reactants, and adventitious water on the success of the catalytic aza-Nazarov reaction.
Collapse
Affiliation(s)
- Bilge Banu Yagci
- Department of Chemistry, Faculty of Science, Bilkent University, Ankara 06800, Turkey
| | - Selin Ezgi Donmez
- Department of Chemistry, Faculty of Science, Bilkent University, Ankara 06800, Turkey
| | - Onur Şahin
- Department of Occupational Health & Safety, Faculty of Health Sciences, Sinop University, Sinop 57000, Turkey
| | - Yunus Emre Türkmen
- Department of Chemistry, Faculty of Science, Bilkent University, Ankara 06800, Turkey,UNAM – National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey
| |
Collapse
|
2
|
Babcock EG, Rahman MS, Taylor JE. Brønsted acid-catalysed desilylative heterocyclisation to form substituted furans. Org Biomol Chem 2022; 21:163-168. [PMID: 36472096 DOI: 10.1039/d2ob01828d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Heterocyclisation of tert-butyldimethylsilyl (TBS) protected γ-hydroxy-α,β-unsaturated ketones catalysed by para-toluenesulfonic acid (p-TSA) to form substituted furans is reported. The reaction proceeds under mild conditions at room temperature in methanol to give a range of furan products (21 examples, up to 98% yield). Mechanistic experiments suggest the reaction proceeds via in situ deprotection followed by catalytic dehydrative heterocyclisation.
Collapse
Affiliation(s)
- Emily G Babcock
- Department of Chemistry, University of Bath, Claverton Down, Bath, Somerset, BA2 7AY, UK.
| | - Md Shafiqur Rahman
- Department of Chemistry, University of Bath, Claverton Down, Bath, Somerset, BA2 7AY, UK.
| | - James E Taylor
- Department of Chemistry, University of Bath, Claverton Down, Bath, Somerset, BA2 7AY, UK.
| |
Collapse
|
3
|
Bera T, Singh B, Gandon V, Saha J. Experimental and Theoretical Investigation of an Azaoxyallyl Cation‐Templated Intramolecular Aryl Amination Leading to Oxindole Derivatives. Chemistry 2022; 28:e202201208. [DOI: 10.1002/chem.202201208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Tishyasoumya Bera
- Department of Biological and Synthetic Chemistry Centre of Biomedical Research (CBMR) SGPGIMS Campus. Raebareli Road Lucknow 226014 Uttar Pradesh India
| | - Bandana Singh
- Department of Biological and Synthetic Chemistry Centre of Biomedical Research (CBMR) SGPGIMS Campus. Raebareli Road Lucknow 226014 Uttar Pradesh India
| | - Vincent Gandon
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO) CNRS UMR 8182, Université Paris-Saclay Bâtiment 420 91405 Orsay cedex France
- Laboratoire de Chimie Moléculaire (LCM) CNRS UMR 9168, Ecole Polytechnique Institut Polytechnique de Paris Route de Saclay 91128 Palaiseau cedex France
| | - Jaideep Saha
- Department of Biological and Synthetic Chemistry Centre of Biomedical Research (CBMR) SGPGIMS Campus. Raebareli Road Lucknow 226014 Uttar Pradesh India
| |
Collapse
|
4
|
Yamada T, Hashimoto Y, Tanaka K, Morita N, Tamura O. Cationic palladium(ii)-catalyzed synthesis of substituted pyridines from α,β-unsaturated oxime ethers. RSC Adv 2022; 12:21548-21557. [PMID: 36043185 PMCID: PMC9351437 DOI: 10.1039/d2ra03875g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/14/2022] [Indexed: 11/21/2022] Open
Abstract
An efficient method for the synthesis of multi-substituted pyridines from β-aryl-substituted α,β-unsaturated oxime ethers and alkenes via Pd-catalyzed C–H activation has been developed. The method, using Pd(OAc)2 and a sterically hindered pyridine ligand, provides access to various multi-substituted pyridines with complete regioselectivity. Mechanistic studies suggest that the pyridine products are formed by Pd-catalyzed electrophilic C–H alkenylation of α,β-unsaturated oxime followed by aza-6π-electrocyclization. The utility of this method is showcased by the synthesis of 4-aryl-substituted pyridine derivatives, which are difficult to synthesize efficiently using previously reported Rh-catalyzed strategies with alkenes. An efficient method for the synthesis of multi-substituted pyridines from α,β-unsaturated oxime ethers via cationic Pd(ii)-catalyzed C–H activation has been developed.![]()
Collapse
Affiliation(s)
- Takahiro Yamada
- Showa Pharmaceutical University Machida Tokyo 194-8543 Japan
| | | | - Kosaku Tanaka
- Showa Pharmaceutical University Machida Tokyo 194-8543 Japan
| | | | - Osamu Tamura
- Showa Pharmaceutical University Machida Tokyo 194-8543 Japan
| |
Collapse
|
5
|
Furugoori M, Yoshida K, Hashimoto Y, Morita N, Tanaka Iii K, Tamura O. Electrophilic Epoxidation of α,β-Unsaturated Oximes with Dioxiranes and Ring Opening of the Epoxides. Chem Pharm Bull (Tokyo) 2021; 69:1010-1016. [PMID: 34305073 DOI: 10.1248/cpb.c21-00533] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
α,β-Unsaturated oximes underwent electrophilic epoxidation with in-situ-generated dimethyldioxirane to give the corresponding epoxides in good yields. This reaction is an example of "carbonyl umpolung" by transformation of α,β-unsaturated ketones to their oximes. Nucleophilic ring-opening reactions of the epoxides afforded α-substituted products. Shi asymmetric epoxidation of the oximes proceeded with moderate enantioselectivity.
Collapse
|
6
|
Ru GX, Zhang TT, Zhang M, Jiang XL, Wan ZK, Zhu XH, Shen WB, Gao GQ. Recent progress towards the transition-metal-catalyzed Nazarov cyclization of alkynes via metal carbenes. Org Biomol Chem 2021; 19:5274-5283. [PMID: 34060570 DOI: 10.1039/d1ob00744k] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
In recent years, transition-metal-catalyzed tandem cyclization reactions of alkynes, especially those involving a metal carbene intermediate, have received worthwhile interest, as this type of reaction does not require the use of risky and potentially explosive diazo compounds as starting materials for carbene generation. A significant and general strategy for the stereospecific synthesis of 5-membered cycles is Nazarov cyclization based on the 4π-conrotatory electrocyclization of a conjugated pentadienyl cation to afford a cyclopentenyl cation. In this review, we introduce an overview of recent advances in the transition-metal-catalyzed Nazarov cyclization of alkynes via a metal carbene intermediate, and categorize these reactions according to the structure of the metal carbene. Our aim is to accelerate advancements in this enchanting area of research.
Collapse
Affiliation(s)
- Guang-Xin Ru
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Ting-Ting Zhang
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Meng Zhang
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Xiao-Lei Jiang
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Zheng-Kai Wan
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Xiu-Hong Zhu
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Wen-Bo Shen
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| | - Guang-Qin Gao
- College of Sciences and College of Forestry, Henan Agricultural University, Zhengzhou, Henan 450002, China.
| |
Collapse
|
7
|
Dong K, Humeidi A, Griffith W, Arman H, Xu X, Doyle MP. Ag
I
‐Catalyzed Reaction of Enol Diazoacetates and Imino Ethers: Synthesis of Highly Functionalized Pyrroles. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202101641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Kuiyong Dong
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Ahmad Humeidi
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Wendell Griffith
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi Arman
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Xinfang Xu
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical Sciences Sun Yat-sen University Guangzhou 510006 China
| | - Michael P. Doyle
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| |
Collapse
|
8
|
Dong K, Humeidi A, Griffith W, Arman H, Xu X, Doyle MP. Ag I -Catalyzed Reaction of Enol Diazoacetates and Imino Ethers: Synthesis of Highly Functionalized Pyrroles. Angew Chem Int Ed Engl 2021; 60:13394-13400. [PMID: 33831277 DOI: 10.1002/anie.202101641] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/24/2021] [Indexed: 12/11/2022]
Abstract
An unprecedented AgI -catalyzed efficient method for the coupling of imino ethers and enol diazoacetates through a [3+2]-cycloaddition/C-O bond cleavage/[1,5]-proton transfer cascade process is reported. The general class of imino ethers that includes oxazolines, benzoxazoles and benzimidates are applicable substrates for these reactions that provide direct access to fully substituted pyrroles with uniformly high chemo- and regioselectivity. High variability in substitution at the pyrrole 2-, 5- and N-positions characterizes this methodology that also presents an entry point for further pyrrole diversification via facile modification of resulting N-functional pyrroles.
Collapse
Affiliation(s)
- Kuiyong Dong
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Ahmad Humeidi
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Wendell Griffith
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Hadi Arman
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Xinfang Xu
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, China
| | - Michael P Doyle
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| |
Collapse
|
9
|
Yamada T, Hashimoto Y, Tanaka K, Morita N, Tamura O. Thioether Ligand-Enabled Cationic Palladium(II)-Catalyzed Electrophilic C-H Arylation of α,β-Unsaturated Oxime Ethers. J Org Chem 2020; 85:12315-12328. [PMID: 32844650 DOI: 10.1021/acs.joc.0c01570] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The use of the cationic palladium(II) catalyst realized electrophilic C-H arylation of α,β-unsaturated O-SEM oximes with arylboronic acids. This Pd-catalyzed electrophilic C-H arylation is facilitated by employing alkyl aryl thioether ligands, and optimization of the ligand structure greatly improves the yield. The resulting α,β-unsaturated oximes would provide access to multisubstituted heterocyclic compounds.
Collapse
Affiliation(s)
- Takahiro Yamada
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | | | - Kosaku Tanaka
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | | | - Osamu Tamura
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| |
Collapse
|
10
|
Donmez SE, Soydaş E, Aydın G, Şahin O, Bozkaya U, Türkmen YE. Aza-Nazarov Cyclization Reactions via Anion Exchange Catalysis. Org Lett 2019; 21:554-558. [PMID: 30985150 DOI: 10.1021/acs.orglett.8b03886] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A catalytic aza-Nazarov cyclization between 3,4-dihydroisoquinolines and α,β-unsaturated acyl chlorides has been developed to access α-methylene-γ-lactam products in good yields (up to 79%) as single diastereomers. The reactions proceed efficiently when AgOTf is used as an anion exchange catalyst with a 20 mol % loading at 80 °C. Computational studies were performed to investigate the reaction mechanism, and the findings support the role of the -TMS group in reducing the reaction barrier of the key cyclization step.
Collapse
Affiliation(s)
- Selin E Donmez
- Department of Chemistry, Faculty of Science , Bilkent University , Ankara , 06800 , Turkey
| | - Emine Soydaş
- Department of Chemistry , Hacettepe University , Ankara , 06800 , Turkey
| | - Gökçen Aydın
- Department of Chemistry, Faculty of Science , Bilkent University , Ankara , 06800 , Turkey
| | - Onur Şahin
- Sinop University , Scientific and Technological Research Application and Research Center , Sinop , 57000 , Turkey
| | - Uğur Bozkaya
- Department of Chemistry , Hacettepe University , Ankara , 06800 , Turkey
| | - Yunus E Türkmen
- Department of Chemistry, Faculty of Science , Bilkent University , Ankara , 06800 , Turkey.,UNAM - National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology , Bilkent University , Ankara , 06800 , Turkey
| |
Collapse
|
11
|
Schlegel M, Schneider C. Rapid Construction of Complex 2-Pyrrolines through Lewis Acid-Catalyzed, Sequential Three-Component Reactions via in Situ-Generated 1-Azaallyl Cations. Org Lett 2018; 20:3119-3123. [DOI: 10.1021/acs.orglett.8b01205] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Marcel Schlegel
- Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| | - Christoph Schneider
- Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| |
Collapse
|
12
|
Kazakova AN, Vasilyev AV. Trifluoromethanesulfonic acid in organic synthesis. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2017. [DOI: 10.1134/s1070428017040017] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
13
|
Okala Amombo GM, Flögel O, Kord Daoroun Kalai S, Schoder S, Warzok U, Reissig HU. Efficient Syntheses of 2,5-Dihydropyrroles, Pyrrolidin-3-ones, and Electron-Rich Pyrroles fromN-Tosylimines and Lithiated Alkoxyallenes. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700073] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Ghislaine Marlyse Okala Amombo
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
- Fachrichtung Chemie und Lebensmittelchemie; Technische Universität Dresden; 01062 Dresden Germany
| | - Oliver Flögel
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | | | - Stefan Schoder
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | - Ulrike Warzok
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | - Hans-Ulrich Reissig
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| |
Collapse
|
14
|
Sudhakar G, Satish K. Nazarov Cyclization of Divinyl and Arylvinyl Epoxides: Application in the Synthesis of Resveratrol-Based Natural Products. Chemistry 2015; 21:6475-80. [DOI: 10.1002/chem.201500362] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Indexed: 11/05/2022]
|
15
|
Palladium-Catalyzed One-Pot Sonogashira Coupling,exo-digCyclization and Hydride Transfer Reaction: Synthesis of Pyridine-Substituted Pyrroles. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201401117] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
16
|
Gujarathi S, Liu X, Song L, Hendrickson H, Zheng G. A mild and efficient AgSbF 6-catalyzed synthesis of fully substituted pyrroles through a sequential propargylation/amination/cycloisomerization reaction. Tetrahedron 2014; 70:5267-5273. [PMID: 25061238 DOI: 10.1016/j.tet.2014.05.073] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Development of an efficient synthesis of fully substituted pyrroles via a sequential as a catalyst. The propargylation/amination/cycloisomerization was accomplished using AgSbF6 one-pot three-component reaction of propargylic alcohols, 1,3-dicarbonyl compounds, and primary amines proceeds at a mild temperature, which prevents the formation of furan by-product. The reaction was also successfully applied to the more basic aliphatic amines with the addition of 1.1 eq. of acetic acid.
Collapse
Affiliation(s)
- Satheesh Gujarathi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Xingui Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Lin Song
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Howard Hendrickson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Guangrong Zheng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| |
Collapse
|
17
|
Dawande SG, Kanchupalli V, Lad BS, Rai J, Katukojvala S. Synergistic Rhodium(II) Carboxylate and Brønsted Acid Catalyzed Multicomponent Reactions of Enalcarbenoids: Direct Synthesis of α-Pyrrolylbenzylamines. Org Lett 2014; 16:3700-3. [DOI: 10.1021/ol501508f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Sudam Ganpat Dawande
- Department of Chemistry, Indian Institute of Science Education & Research, Bhopal, Madhya Pradesh 462066, India
| | - Vinaykumar Kanchupalli
- Department of Chemistry, Indian Institute of Science Education & Research, Bhopal, Madhya Pradesh 462066, India
| | - Bapurao Sudam Lad
- Department of Chemistry, Indian Institute of Science Education & Research, Bhopal, Madhya Pradesh 462066, India
| | - Jyoti Rai
- Department of Chemistry, Indian Institute of Science Education & Research, Bhopal, Madhya Pradesh 462066, India
| | - Sreenivas Katukojvala
- Department of Chemistry, Indian Institute of Science Education & Research, Bhopal, Madhya Pradesh 462066, India
| |
Collapse
|
18
|
Abstract
This review discusses novel Nazarov cyclization variations and their application to the synthesis of complex molecules.
Collapse
Affiliation(s)
- Martin J. Di Grandi
- Department of Natural Sciences
- Fordham University at Lincoln Center
- New York, USA
| |
Collapse
|
19
|
Su C, Hopson R, Williard PG. Characterization of cyclopentyllithium and cyclopentyllithium tetrahydrofuran complex. J Am Chem Soc 2013; 135:12400-6. [PMID: 23875807 DOI: 10.1021/ja4059102] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The solid-state structures of unsolvated, hexameric cyclopentyllithium and tetrameric cyclopentyllithium tetrahydrofuran solvate were determined by single-crystal X-ray diffraction. Cyclopentyllithium easily crystallized in hydrocarbon solvents. Solution-state structural analyses of cyclopentyllithium and cyclopentyllithium-tetrahydrofuran complexes in toluene-d8 were also carried out by diffusion-ordered NMR spectroscopy with diffusion coefficient-formula weight correlation analyses and other one- and two-dimensional NMR techniques. The solution-state studies suggest that unsolvated cyclopentyllithium exists as hexamer and tetramer equilibrating with each other. Upon solvation with tetrahydrofuran, cyclopentyllithium exists mostly as a tetrahydrofuran tetrasolvated tetramer.
Collapse
Affiliation(s)
- Chicheung Su
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | | | | |
Collapse
|
20
|
Alford JS, Spangler JE, Davies HML. Conversion of Cyclic Ketones to 2,3-Fused Pyrroles and Substituted Indoles. J Am Chem Soc 2013; 135:11712-5. [DOI: 10.1021/ja405043g] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Joshua S. Alford
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia
30322, United States
| | - Jillian E. Spangler
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia
30322, United States
| | - Huw M. L. Davies
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia
30322, United States
| |
Collapse
|
21
|
Jiao L, Bach T. Palladium-Catalyzed Direct CH Alkylation of Electron-Deficient Pyrrole Derivatives. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201301154] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
22
|
Jiao L, Bach T. Palladium-Catalyzed Direct CH Alkylation of Electron-Deficient Pyrrole Derivatives. Angew Chem Int Ed Engl 2013; 52:6080-3. [DOI: 10.1002/anie.201301154] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Indexed: 11/10/2022]
|
23
|
Parr BT, Green SA, Davies HML. Rhodium-Catalyzed Conversion of Furans to Highly Functionalized Pyrroles. J Am Chem Soc 2013; 135:4716-8. [DOI: 10.1021/ja401386z] [Citation(s) in RCA: 206] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Brendan T. Parr
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - Samantha A. Green
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - Huw M. L. Davies
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| |
Collapse
|
24
|
Zheng H, Lejkowski M, Hall DG. Mild boronic acid catalyzed Nazarov cyclization of divinyl alcohols in tandem with Diels–Alder cycloaddition. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2012.10.100] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
25
|
Narayan R, Daniliuc CG, Würthwein EU. Preparation of NH-Pyrroles under Superelectrophilic Conditions by an Aza-Nazarov Reaction Cascade with Indole as Neutral Leaving Group: Experiment and Theory. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200913] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|