1
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R. Yaya A, Girard M, Belkhadem K, Piard R, Decken A, Choinière C, Cloutier PL, Lesage J, Breau L. Synthesis of 3-Alkyl Oxazolidines, Derived from 2-Hydroxymethyl Piperidine, as Analytical Standards for the Analysis of Volatile Aldehydes in the Workplace. ACS OMEGA 2023; 8:26793-26805. [PMID: 37546669 PMCID: PMC10398864 DOI: 10.1021/acsomega.3c00961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/30/2023] [Indexed: 08/08/2023]
Abstract
Hexahydro-3-alkyl-3H-oxazolo[3,4-a]pyridines 4-15 for the quantitative analysis of various aldehydes were obtained in good yield via the condensation reaction of 2-hydroxymethylpiperidine (2-HMP) with aldehydes under mild conditions. When acrolein was used, the bicyclic 17 was obtained. This novel compound has suitable physical characteristics for an analytical standard. The hexahydro-3-vinyl-3H-oxazolo[3,4-a]pyridine 16 can be obtained at higher temperatures using an excess of acrolein (3 equiv). Following the same procedure as for 16, but with an excess of 2-HMP (2 equiv), a diastereomeric mixture of 18/19, which are both bisadducts of 2-HMP with acrolein, was obtained. The latter mixture can be easily converted into pure 18. Mechanistically, a thorough 1H-NMR study did not show any evidence that the condensation reaction proceeded via an enamine. The reaction probably proceeded through an elusive hemiaminal and fleeting iminium ion, which underwent subsequent cyclization to give hexahydro-3-alkyl-3H-oxazolo[3,4-a]pyridines 4-16. The reaction pathways for the preparation of 4-18 are described.
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Affiliation(s)
- Amadou R. Yaya
- Département
de chimie, Université du Québec
à Montréal, CP. 8888, Succ. Centre-Ville, Montreal, PQ H3C 3P8, Canada
| | - Martin Girard
- Département
de chimie, Université du Québec
à Montréal, CP. 8888, Succ. Centre-Ville, Montreal, PQ H3C 3P8, Canada
| | - Karima Belkhadem
- Département
de chimie, Université du Québec
à Montréal, CP. 8888, Succ. Centre-Ville, Montreal, PQ H3C 3P8, Canada
- Department
of Chemistry University of Sciences and
Technology Mohamed Boudiaf, P.O. Box
1505 El-M’naouer, 31000 Oran, Algeria
| | - Rémi Piard
- Département
de chimie, Université du Québec
à Montréal, CP. 8888, Succ. Centre-Ville, Montreal, PQ H3C 3P8, Canada
| | - Andreas Decken
- Department
of Chemistry University of New Brunswick P.O. Box 45222 Fredericton, NB E3A 6E2, Canada
| | - Catherine Choinière
- Institut
de recherche Robert-Sauvé en santé et en sécurité
du travail, 505 Ouest De Blvd Maisonneuve, Montréal, Québec H3A 3C2, Canada
| | - Pierre Luc Cloutier
- Institut
de recherche Robert-Sauvé en santé et en sécurité
du travail, 505 Ouest De Blvd Maisonneuve, Montréal, Québec H3A 3C2, Canada
| | - Jacques Lesage
- Département
de chimie, Université du Québec
à Montréal, CP. 8888, Succ. Centre-Ville, Montreal, PQ H3C 3P8, Canada
| | - Livain Breau
- Département
de chimie, Université du Québec
à Montréal, CP. 8888, Succ. Centre-Ville, Montreal, PQ H3C 3P8, Canada
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2
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Conceptual design and cost-efficient environmentally Benign synthesis of beta-lactams. PHYSICAL SCIENCES REVIEWS 2022. [DOI: 10.1515/psr-2021-0088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Stereoselective preparation of diverse trans and cis β-lactams following different experimental conditions are executed. A variety of circumstances are critically analyzed. It has been found that the stereochemistry of the products depends on a number of parameters including the conditions of the procedures, composition of the Schiff bases and acid chlorides or equivalents, method of addition of the reactants, temperature of the process and nature of the media. Using some of the compounds and methods as described herein, a number of useful chemical transformations for the preparation of heterocycles are achieved. These methods include indium-catalyzed glycosylation of amino β-lactams, preparation of pyrrole-substituted β-lactams, cycloaddition with sterically congested Schiff bases towards β-lactams, Michael reaction for the preparation of polycyclic oxazepenes and synthesis of two chiral isomers of the thienamycin side chain. Most of the products are obtained stereospecifically and in optically active forms. Many reactions described here are catalytic and therefore, these are environmentally friendly.
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3
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Gharpure SJ, Nanda SK, Fartade DJ, Vishwakarma DS. Domino Hydroalkoxylation‐[4+2]‐Cycloaddition for Stereoselective Synthesis of 1,4‐Heterocycle‐Fused Chromenes: Rapid Access to the [6‐6‐7‐6] Tetracyclic Core of Cytorhizhins B–D. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901565] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Santosh J. Gharpure
- Department of Chemistry Indian Institute of Technology Bombay Powai 400076 Mumbai – India
| | - Santosh K. Nanda
- Department of Chemistry Indian Institute of Technology Bombay Powai 400076 Mumbai – India
| | - Dipak J. Fartade
- Department of Chemistry Indian Institute of Technology Bombay Powai 400076 Mumbai – India
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4
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Gharpure SJ, Nanda SK, Fartade DJ. Expeditious diastereoselective synthesis of medium ring heterocycle-fused chromenes via tandem 8/9-endo-dig and 8-exo-dig hydroalkoxylation-formal-[4 + 2] cycloaddition. Org Biomol Chem 2019; 17:8806-8810. [PMID: 31556431 DOI: 10.1039/c9ob02030f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first examples of highly diastereoselective tandem 8/9-endo-dig and 8-exo-dig hydroalkoxylation-formal-[4 + 2] cycloaddition are described for the synthesis of medium ring heterocycle-fused chromenes. TMS-alkynols preferred the exo-dig mode of hydroalkoxylation over the endo-dig mode leading to spiro-cyclic chromenes. The method could be used for the synthesis of linearly-fused ladder-like polyethers. A thia-heterocycle-fused chromene could be transformed into a complex bridged tricyclic ketal by a tandem carbene-insertion-[2,3]-sigmatropic shift.
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Affiliation(s)
- Santosh J Gharpure
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai - 400076, India.
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5
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New chiral morpholine-pyrrolidine ligands affecting asymmetric selectivity in copper catalyzed Henry reaction. Tetrahedron Lett 2019. [DOI: 10.1016/j.tetlet.2019.01.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Wang Y, Zhang WY, You SL. Ketones and Aldehydes as O-Nucleophiles in Iridium-Catalyzed Intramolecular Asymmetric Allylic Substitution Reaction. J Am Chem Soc 2019; 141:2228-2232. [DOI: 10.1021/jacs.8b13182] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Ye Wang
- State Key Laboratory
of Organometallic Chemistry, Center for Excellence in Molecular Synthesis,
Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, 345 Lingling Lu, Shanghai 200032, China
| | - Wen-Yun Zhang
- State Key Laboratory
of Organometallic Chemistry, Center for Excellence in Molecular Synthesis,
Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, 345 Lingling Lu, Shanghai 200032, China
| | - Shu-Li You
- State Key Laboratory
of Organometallic Chemistry, Center for Excellence in Molecular Synthesis,
Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai Institute of Organic Chemistry, 345 Lingling Lu, Shanghai 200032, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 30072, China
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7
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Borah M, Borthakur U, Saikia AK. Diastereoselective Synthesis of Substituted Morpholines from N-Tethered Alkenols: Total Synthesis of (±)-Chelonin A. J Org Chem 2017; 82:1330-1339. [DOI: 10.1021/acs.joc.6b02260] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Madhurjya Borah
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Upasana Borthakur
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Anil K. Saikia
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
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8
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Ghosh P, Deka MJ, Saikia AK. Lewis acid mediated intramolecular C–O bond formation of alkanol-epoxide leading to substituted morpholine and 1,4-oxazepane derivatives: total synthesis of (±)–Viloxazine. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.12.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Deka MJ, Indukuri K, Sultana S, Borah M, Saikia AK. Synthesis of Five-, Six-, and Seven-Membered 1,3- and 1,4-Heterocyclic Compounds via Intramolecular Hydroalkoxylation/Hydrothioalkoxylation of Alkenols/Thioalkenols. J Org Chem 2015; 80:4349-59. [DOI: 10.1021/acs.joc.5b00049] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Manash J. Deka
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
| | - Kiran Indukuri
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
| | - Sabera Sultana
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
| | - Madhurjya Borah
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
| | - Anil K. Saikia
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
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Kaladevi S, Thirupathi A, Sridhar J, Muthusubramanian S. Copper catalysed [3 + 2] cycloaddition with concomitant annulation: formation of 2,4-diaryl-1,4-oxazepan-7-ones via a ketenimine route. RSC Adv 2014. [DOI: 10.1039/c4ra08008d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A novel strategy of copper catalyzed cascade reaction involving intramolecular nucleophilic addition to N-sulfonylketenimine gratifyingly furnishing 1,4-diaryl oxazepan-7-one has been described.
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Affiliation(s)
- Selvam Kaladevi
- Department of Organic Chemistry
- School of Chemistry
- Madurai Kamaraj University
- Madurai–625 021, India
| | - Arumugam Thirupathi
- Department of Organic Chemistry
- School of Chemistry
- Madurai Kamaraj University
- Madurai–625 021, India
| | - Jeyaraman Sridhar
- Department of Organic Chemistry
- School of Chemistry
- Madurai Kamaraj University
- Madurai–625 021, India
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11
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Gharpure SJ, Prasad JVK. Stereoselective Synthesis of Substituted 1,4-Oxazepanes by Intramolecular Reductive Etherification. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300135] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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12
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Eftekhari-Sis B, Zirak M, Akbari A. Arylglyoxals in Synthesis of Heterocyclic Compounds. Chem Rev 2013; 113:2958-3043. [DOI: 10.1021/cr300176g] [Citation(s) in RCA: 228] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Bagher Eftekhari-Sis
- Department of Chemistry, Faculty
of Science, University of Maragheh, Golshahr,
P.O. Box. 55181-83111, Maragheh, Iran
| | - Maryam Zirak
- Department of Chemistry, Payame Noor University, P.O. Box 19395-3697, Tehran,
Iran
| | - Ali Akbari
- Department of Chemistry, Faculty
of Science, University of Maragheh, Golshahr,
P.O. Box. 55181-83111, Maragheh, Iran
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13
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Zhou R, Wang J, Duan C, He Z. Phosphine-Triggered Tandem Annulation between Morita–Baylis–Hillman Carbonates and Dinucleophiles: Facile Syntheses of Oxazepanes, Thiazepanes, and Diazepanes. Org Lett 2012; 14:6134-7. [DOI: 10.1021/ol302696e] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rong Zhou
- The State Key Laboratory of Elemento-Organic Chemistry and Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China
| | - Jianfang Wang
- The State Key Laboratory of Elemento-Organic Chemistry and Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China
| | - Chong Duan
- The State Key Laboratory of Elemento-Organic Chemistry and Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China
| | - Zhengjie He
- The State Key Laboratory of Elemento-Organic Chemistry and Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China
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14
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Heasley B. Chemical synthesis of the cardiotonic steroid glycosides and related natural products. Chemistry 2012; 18:3092-120. [PMID: 22354477 DOI: 10.1002/chem.201103733] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The active components from the extracts of Digitalis, cardiotonic steroid glycosides, have been ingested by humans for more than 200 years as a medicinal therapy for heart failure and abnormal heart rhythms. The positive inotropic activity of the cardiotonic steroids that mediates clinically useful physiological effects in patients has been attributed largely to a high affinity inhibitory interaction with the extracellular surface of the membrane-bound sodium pump (Na(+)/K(+)-ATPase). However, previously unrecognized intracellular signaling pathways continue to be uncovered. This Review examines both partial and de novo synthetic approaches to the medicinally important and structurally captivating cardenolide and bufadienolide steroid families, with an emphasis on the stereocontrolled construction of the pharmacophoric aglycone (genin) framework.
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Affiliation(s)
- Brian Heasley
- Scynexis, Inc. P. O. Box 12878, Research Triangle Park, NC 27709-2878, USA.
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15
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Abstract
Terpenes and alkaloids are ever-growing classes of natural products that provide new molecular structures which inspire chemists and possess a broad range of biological activity. Terpenoid-alkaloids originate from the same prenyl units that construct terpene skeletons. However, during biosynthesis, a nitrogen atom (or atoms) is introduced in the form of β-aminoethanol, ethylamine, or methylamine. Nitrogen incorporation can occur either before, during, or after the cyclase phase. The outcome of this unique biosynthesis is the formation of natural products containing unprecedented structures. These complex structural motifs expose current limitations in organic chemistry, thus providing opportunities for invention. This review focuses on total syntheses of terpenoid-alkaloids and unique issues presented by this class of natural products. More specifically, it examines how these syntheses relate to the way terpenoid-alkaloids are made in Nature. Developments in chemistry that have facilitated these syntheses are emphasized, as well as chemical technology needed to conquer those that evade synthesis.
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Affiliation(s)
- Emily C. Cherney
- Department of Chemistry, The Scripps Research Institute 10550 N. Torrey Pines Rd, La Jolla, CA 92037 phone: (+1) 858-784-7370 fax: (+1) 858-784-7375
| | - Phil S. Baran
- Department of Chemistry, The Scripps Research Institute 10550 N. Torrey Pines Rd, La Jolla, CA 92037 phone: (+1) 858-784-7370 fax: (+1) 858-784-7375
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16
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Samanta K, Panda G. One pot synthesis of amino acid derived chiral disubstituted morpholines and 1,4-oxazepanes via tandem aziridine/epoxide ring opening sequences. Org Biomol Chem 2011; 9:7365-71. [DOI: 10.1039/c1ob05462g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Das SK, Srivastava AK, Panda G. A new route to 1,4-oxazepanes and 1,4-diazepanes from Garner aldehyde. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.01.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Ghorai MK, Shukla D, Das K. Enantioselective Syntheses of Morpholines and Their Homologues via SN2-Type Ring Opening of Aziridines and Azetidines with Haloalcohols. J Org Chem 2009; 74:7013-22. [DOI: 10.1021/jo901297d] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manas K. Ghorai
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | - Dipti Shukla
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | - Kalpataru Das
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
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19
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Arslan H, Demircan A. Structure and vibrational frequencies of 6-chloro-8-thia-1,4-epoxybicyclo[4.3.0]non-2-ene: density functional theory study. MOLECULAR SIMULATION 2008. [DOI: 10.1080/08927020701632862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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The Molecular Structure and Vibrational Spectrum of 6-bromo-8-thia-1,4-epoxybicyclo[4.3.0]non-2-ene. Int J Mol Sci 2007. [DOI: 10.3390/i8111064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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21
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Reactions of electron-withdrawing thiophene 1,1-dioxides with furans. A novel reaction pathway. Russ Chem Bull 2006. [DOI: 10.1007/s11172-006-0318-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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22
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Clark SM, Osborn HM. Synthetic entry to functionalised morpholines and [1,4]-oxazepanes via reductive amination reactions of carbohydrate derived dialdehydes. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.10.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Marsault E, Toró A, Nowak P, Deslongchamps P. The transannular Diels–Alder strategy: applications to total synthesis. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00121-1] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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25
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26
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Reaction of methylcerium reagent with tertiary amides: Synthesis of saturated and unsaturated ketones from tertiary amides. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)00959-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Kurosu M, Marcin LR, Grinsteiner TJ, Kishi Y. Total Synthesis of (±)-Batrachotoxinin A. J Am Chem Soc 1998. [DOI: 10.1021/ja981258g] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michio Kurosu
- Department of Chemistry and Chemical Biology Harvard University, Cambridge, Massachusetts 02138
| | - Lawrence R. Marcin
- Department of Chemistry and Chemical Biology Harvard University, Cambridge, Massachusetts 02138
| | - Timothy J. Grinsteiner
- Department of Chemistry and Chemical Biology Harvard University, Cambridge, Massachusetts 02138
| | - Yoshito Kishi
- Department of Chemistry and Chemical Biology Harvard University, Cambridge, Massachusetts 02138
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Pontén F, Magnusson G. Synthesis of Polycyclic Oxanorbornanes via a Sequential Epoxyhexopyranoside Ring Contraction-Intramolecular Diels-Alder Reaction. J Org Chem 1997; 62:7978-7983. [PMID: 11671900 DOI: 10.1021/jo970667c] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ring contraction of methyl 2,3-anhydro-6-deoxy-6-(furfurylthio)-alpha-D-allopyranoside with LiBr/TMU in boiling toluene gave the corresponding alpha,beta-unsaturated furanosidic aldehyde 1 together with a small amount of the corresponding oxanorbornene Diels-Alder adduct 2. Pumping a mixture of heptane and Et(3)N slowly through a SiO(2) column containing 1 and 2 shifted the ratio strongly toward 2. The products were eluted from the column by EtOAc/EtOH and chromatographed to give pure 2 and 1 in 79% and 15% yield, respectively. Compound 2 was submitted to a number of oxidations and reductions, which gave the oxanorbornanes 4-15. The structures were determined by 2D (1)H and (13)C NMR techniques and by a single-crystal X-ray investigation of compound 5.
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Affiliation(s)
- Fritiof Pontén
- Organic Chemistry 2, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, S-221 00 Lund, Sweden
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31
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Taber DF, Song Y. Stereocontrolled Assembly of Cis or Trans Angularly Substituted Hydrindenes by the Unactivated Intramolecular Diels-Alder Reaction. J Org Chem 1996; 61:7508-7512. [PMID: 11667681 DOI: 10.1021/jo9610974] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The unactivated intramolecular Diels-Alder reaction has become a powerful tool for the construction of polycyclic natural products. Nevertheless, the factors that govern diastereoselectivity in these cyclizations have not been fully understood. We here report that through the choice of the proper substituents, it is possible to make the unactivated intramolecular Diels-Alder reaction proceed to give either the cis angularly-substituted hydrindene 12b or the trans product 19a.
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Affiliation(s)
- Douglass F. Taber
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716
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32
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Maki S, Konno K, Takayama H. A novel approach to functionalized polycyclic systems; new aspects of the Diels–Alder reactions of 2-acyl derivative of 4H,6H-thieno[3,4-c]furan 5,5-dioxide. ACTA ACUST UNITED AC 1995. [DOI: 10.1039/c39950002025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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