1
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Ikeuchi K, Haraguchi S, Fujii R, Yamada H, Suzuki T, Tanino K. Total Synthesis of (+)-Coriamyrtin via a Desymmetrizing Strategy Involving a 1,3-Cyclopentanedione Moiety. Org Lett 2023; 25:2751-2755. [PMID: 36853202 DOI: 10.1021/acs.orglett.3c00249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
We describe the total synthesis of (+)-coriamyrtin, which bears a highly functionalized cis-hydrindane skeleton and is a widely known neurotoxin of the Coriariaceae family. Our synthetic strategy involves the highly stereoselective construction of the cis-hydrindane skeleton via a desymmetrizing strategy involving a 1,3-cyclopentanedione moiety using an intramolecular aldol reaction and the formation of the 1,3-diepoxide moiety of coriamyrtin through the elaborate functionalization of the cyclopentane ring in the bicyclic structure.
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Affiliation(s)
- Kazutada Ikeuchi
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Shota Haraguchi
- School of Science and Technology, Kwansei Gakuin University, Sanda 669-1337, Japan
| | - Ryo Fujii
- School of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Hidetoshi Yamada
- School of Science and Technology, Kwansei Gakuin University, Sanda 669-1337, Japan
| | - Takahiro Suzuki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Keiji Tanino
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
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2
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Nugent TC, Vos AE, Hussain I, El Damrany Hussein HA, Goswami F. A 2000 to 2020 Practitioner's Guide to Chiral Amine‐Based Enantioselective Aldol Reactions: Ketone Substrates, Best Methods, in Water Reaction Environments, and Defining Nuances. European J Org Chem 2022. [DOI: 10.1002/ejoc.202100529] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Thomas C. Nugent
- Department of Life Sciences and Chemistry Jacobs University Bremen 28759 Bremen Germany
| | - Alice E. Vos
- Department of Life Sciences and Chemistry Jacobs University Bremen 28759 Bremen Germany
| | - Ishtiaq Hussain
- Department of Pharmacy Abbottabad University of Science and Technology Havelian Abbottabad 22010 Pakistan
| | | | - Falguni Goswami
- Department of Life Sciences and Chemistry Jacobs University Bremen 28759 Bremen Germany
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3
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Organocatalyst Design for the Stereoselective Annulation towards Bicyclic Diketones and Analogues. Symmetry (Basel) 2022. [DOI: 10.3390/sym14020355] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The Wieland–Miescher ketone, Hajos–Parrish–Eder–Sauer–Wiechert ketone, and their analogues are bicyclic diketones essential as building blocks for the synthesis of several natural and bioactive molecules. For this reason, since 1971, when Hajos and Parrish and Eder, Sauer, and Wiechert reported the stereoselective synthesis of these compounds promoted by L-proline, numerous methodologies and organocatalysts have been studied over the years with the aim of identifying increasingly efficient asymmetrical syntheses of these bicyclic ketones. This review will outline the methodological and stereochemical features of the organocatalytic stereoselective synthesis of these bicyclic scaffolds based on the different organocatalysts employed from 1971 until today. Particular emphasis will be given to the structural features of the catalysts and to the reaction conditions.
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4
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Kühlborn J, Groß J, Opatz T. Making natural products from renewable feedstocks: back to the roots? Nat Prod Rep 2020; 37:380-424. [DOI: 10.1039/c9np00040b] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review highlights the utilization of biomass-derived building blocks in the total synthesis of natural products.
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Affiliation(s)
- Jonas Kühlborn
- Institute of Organic Chemistry
- Johannes Gutenberg University
- 55128 Mainz
- Germany
| | - Jonathan Groß
- Institute of Organic Chemistry
- Johannes Gutenberg University
- 55128 Mainz
- Germany
| | - Till Opatz
- Institute of Organic Chemistry
- Johannes Gutenberg University
- 55128 Mainz
- Germany
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5
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Smaligo AJ, Swain M, Quintana JC, Tan MF, Kim DA, Kwon O. Hydrodealkenylative C(sp 3)-C(sp 2) bond fragmentation. Science 2019; 364:681-685. [PMID: 31097667 DOI: 10.1126/science.aaw4212] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 03/14/2019] [Indexed: 12/19/2022]
Abstract
Chemical synthesis typically relies on reactions that generate complexity through elaboration of simple starting materials. Less common are deconstructive strategies toward complexity-particularly those involving carbon-carbon bond scission. Here, we introduce one such transformation: the hydrodealkenylative cleavage of C(sp3)-C(sp2) bonds, conducted below room temperature, using ozone, an iron salt, and a hydrogen atom donor. These reactions are performed in nonanhydrous solvents and open to the air; reach completion within 30 minutes; and deliver their products in high yields, even on decagram scales. We have used this broadly functionality tolerant transformation to produce desirable synthetic intermediates, many of which are optically active, from abundantly available terpenes and terpenoid-derived precursors. We have also applied it in the formal total syntheses of complex molecules.
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Affiliation(s)
- Andrew J Smaligo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Manisha Swain
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Jason C Quintana
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Mikayla F Tan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Danielle A Kim
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ohyun Kwon
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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6
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Xu EJ, Song Y, Wei ZL, Wang R, Duan HF, Lin YJ, Yang QB, Li YX. Novel chiral proline-based organocatalysts with amide and thiourea–amine units for highly efficient asymmetric aldol reaction in saturated brine without additives. CAN J CHEM 2019. [DOI: 10.1139/cjc-2018-0352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A series of novel proline-based organocatalysts with amide and thiourea-amine units (7a–7f) were developed and evaluated in the asymmetric aldol reaction of 4-nitrobenzaldehyde with cyclohexanone. The organocatalyst (7c or 7d, 5 mol%) exhibited efficient catalytic activity to afford aldol products in high diastereoselectivity (up to >99:1), enantioselectivity (up to >99%), and yield (up to >96%) at 0 °C in saturated brine without adding an acid. Aldol products of benzaldehyde derivatives almost universally provide high diastereoselectivity and enantioselectivity.
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Affiliation(s)
- En-Jie Xu
- College of Chemistry, Jilin University, Changchun 130012, China
- College of Materials Science and Engineering, Jilin Institute of Chemical Technology, Jilin 132022, China
| | - Yan Song
- College of Materials Science and Engineering, Jilin Institute of Chemical Technology, Jilin 132022, China
| | - Zhong-Lin Wei
- College of Chemistry, Jilin University, Changchun 130012, China
| | - Rui Wang
- College of Chemistry, Jilin University, Changchun 130012, China
| | - Hai-Feng Duan
- College of Chemistry, Jilin University, Changchun 130012, China
| | - Ying-Jie Lin
- College of Chemistry, Jilin University, Changchun 130012, China
| | - Qing-Biao Yang
- College of Chemistry, Jilin University, Changchun 130012, China
| | - Yao-Xian Li
- College of Chemistry, Jilin University, Changchun 130012, China
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7
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Clot-Almenara L, Rodríguez-Escrich C, Pericàs MA. Desymmetrisation of meso-diones promoted by a highly recyclable polymer-supported chiral phosphoric acid catalyst. RSC Adv 2018; 8:6910-6914. [PMID: 35540356 PMCID: PMC9078317 DOI: 10.1039/c7ra13471a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/04/2018] [Indexed: 11/21/2022] Open
Abstract
A polystyrene-supported BINOL-derived chiral phosphoric acid has been applied to the desymmetrisation of meso-diones to produce enantioenriched cyclohexenones. The catalytic resin has proven highly active and robust, giving rise to Hajos–Parrish or Wieland–Miescher type products in good yields and enantioselectivities, while allowing for extended recycling. A polystyrene-supported, recyclable, BINOL-derived chiral phosphoric acid has been applied to the desymmetrization of meso-diones to produce enantioenriched cyclohexenones.![]()
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Affiliation(s)
- Lidia Clot-Almenara
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology
- 43007 Tarragona
- Spain
| | - Carles Rodríguez-Escrich
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology
- 43007 Tarragona
- Spain
| | - Miquel A. Pericàs
- Institute of Chemical Research of Catalonia (ICIQ)
- The Barcelona Institute of Science and Technology
- 43007 Tarragona
- Spain
- Departament de Química Inorgànica i Orgànica
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8
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Pan L, Ding X, Ding J, Li D, Chen J, Zuo X, An R. Design and Synthesis of L-Proline Derivatives as Enantioselective Organocatalysts for Synthesis of the (S
)-Wieland-Miescher Ketone. ChemistrySelect 2017. [DOI: 10.1002/slct.201702075] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Li Pan
- State Key Laboratory of NBC Protection for Civilian; Beijing 102205 China
- Institute of Pharmaceutical Chemistry; Beijing 102205 China
| | - Xiaoqin Ding
- State Key Laboratory of NBC Protection for Civilian; Beijing 102205 China
- Institute of Pharmaceutical Chemistry; Beijing 102205 China
| | - Junjie Ding
- Institute of Pharmaceutical Chemistry; Beijing 102205 China
| | - Dayu Li
- Institute of Pharmaceutical Chemistry; Beijing 102205 China
| | - Jisheng Chen
- Institute of Pharmaceutical Chemistry; Beijing 102205 China
| | - Xialong Zuo
- COE Lab; Agilent Technologies (China) Co., Ltd.; Beijing 100102 China
| | - Rong An
- COE Lab; Agilent Technologies (China) Co., Ltd.; Beijing 100102 China
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9
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Armaly AM, Bar S, Schindler CS. Aluminum Chloride-Mediated Dieckmann Cyclization for the Synthesis of Cyclic 2-Alkyl-1,3-alkanediones: One-Step Synthesis of the Chiloglottones. Org Lett 2017; 19:3958-3961. [DOI: 10.1021/acs.orglett.7b01622] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ahlam M. Armaly
- Department of Chemistry,
Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Sukanta Bar
- Department of Chemistry,
Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Corinna S. Schindler
- Department of Chemistry,
Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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10
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Schneider LM, Schmiedel VM, Pecchioli T, Lentz D, Merten C, Christmann M. Asymmetric Synthesis of Carbocyclic Propellanes. Org Lett 2017; 19:2310-2313. [PMID: 28445060 DOI: 10.1021/acs.orglett.7b00836] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A modular synthesis of functionalized carbocyclic propellanes was developed. Formation of the first of two quaternary bridgehead centers has been achieved by desymmetrization of prostereogenic ketones by either Hajos-Parrish-Eder-Sauer-Wiechert-type processes or Werner's catalytic asymmetric Wittig reaction. The obtained bicyclic enones were subjected to conjugate additions upon which the remaining ring was formed by olefin metathesis. All bridges are amenable to further derivatization, which renders those compounds useful as central units in fragment-based drug discovery or as ligand scaffolds.
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Affiliation(s)
- Lisa M Schneider
- Institut für Chemie und Biochemie, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
| | - Volker M Schmiedel
- Institut für Chemie und Biochemie, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
| | - Tommaso Pecchioli
- Institut für Chemie und Biochemie, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
| | - Dieter Lentz
- Institut für Chemie und Biochemie, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
| | - Christian Merten
- Ruhr-Universität Bochum , Organische Chemie 2, Universitätsstraße 150, 44801 Bochum, Germany
| | - Mathias Christmann
- Institut für Chemie und Biochemie, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
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11
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Xu HS, Ding SY, An WK, Wu H, Wang W. Constructing Crystalline Covalent Organic Frameworks from Chiral Building Blocks. J Am Chem Soc 2016; 138:11489-92. [DOI: 10.1021/jacs.6b07516] [Citation(s) in RCA: 226] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Hai-Sen Xu
- State
Key Laboratory of Applied Organic Chemistry, College of Chemistry
and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - San-Yuan Ding
- State
Key Laboratory of Applied Organic Chemistry, College of Chemistry
and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Wan-Kai An
- State
Key Laboratory of Applied Organic Chemistry, College of Chemistry
and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Han Wu
- State
Key Laboratory of Applied Organic Chemistry, College of Chemistry
and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Wei Wang
- State
Key Laboratory of Applied Organic Chemistry, College of Chemistry
and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China
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12
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Zeng XP, Cao ZY, Wang YH, Zhou F, Zhou J. Catalytic Enantioselective Desymmetrization Reactions to All-Carbon Quaternary Stereocenters. Chem Rev 2016; 116:7330-96. [DOI: 10.1021/acs.chemrev.6b00094] [Citation(s) in RCA: 468] [Impact Index Per Article: 58.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Xing-Ping Zeng
- Shanghai
Key Laboratory of Green Chemistry and Chemical Processes, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Zhong-Yan Cao
- Shanghai
Key Laboratory of Green Chemistry and Chemical Processes, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Yu-Hui Wang
- Shanghai
Key Laboratory of Green Chemistry and Chemical Processes, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Feng Zhou
- Shanghai
Key Laboratory of Green Chemistry and Chemical Processes, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Jian Zhou
- Shanghai
Key Laboratory of Green Chemistry and Chemical Processes, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
- State
Key Laboratory and Institute of Elemento-organic Chemistry, Nankai University, Tianjin 300071, P. R. China
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13
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Ötvös SB, Szloszár A, Mándity IM, Fülöp F. Heterogeneous Dipeptide-Catalyzed α-Amination of Aldehydes in a Continuous-Flow Reactor: Effect of Residence Time on Enantioselectivity. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201500375] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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15
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Bifunctional organocatalysts based on a carbazole scaffold for the synthesis of the Hajos–Wiechert and Wieland–Miescher ketones. Tetrahedron 2015. [DOI: 10.1016/j.tet.2014.12.079] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Guo W, Wei J, Liu Y, Li C. Construction of anti-1,2-diols bearing chiral tertiary alcohol moiety using free hydroxyacetone as aldol donor by imidazole-based prolineamide catalyst. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.07.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Msutu A, Hunter R. Acetals: a new organocatalysis chemotype for one-pot enantioselective α-amination. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.02.097] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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18
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Liu N, Martin A, Robert F, Vincent JM, Landais Y, Vignolle J, Cramail H, Taton D. Polyaldol Synthesis by Direct Organocatalyzed Crossed Polymerization of Bis(ketones) and Bis(aldehydes). Macromolecules 2014. [DOI: 10.1021/ma402108y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Na Liu
- University of Bordeaux, LCPO, UMR 5629, F-33600 Pessac, France
- CNRS, LCPO, UMR 5629, F-33600 Pessac, France
| | - Anthony Martin
- University of Bordeaux, ISM, UMR 5255, 33400 Talence, France
- CNRS, ISM, UMR 5255, 33400 Talence, France
| | - Frédéric Robert
- University of Bordeaux, ISM, UMR 5255, 33400 Talence, France
- CNRS, ISM, UMR 5255, 33400 Talence, France
| | - Jean-Marc Vincent
- University of Bordeaux, ISM, UMR 5255, 33400 Talence, France
- CNRS, ISM, UMR 5255, 33400 Talence, France
| | - Yannick Landais
- University of Bordeaux, ISM, UMR 5255, 33400 Talence, France
- CNRS, ISM, UMR 5255, 33400 Talence, France
| | - Joan Vignolle
- University of Bordeaux, LCPO, UMR 5629, F-33600 Pessac, France
- CNRS, LCPO, UMR 5629, F-33600 Pessac, France
| | - Henri Cramail
- University of Bordeaux, LCPO, UMR 5629, F-33600 Pessac, France
- CNRS, LCPO, UMR 5629, F-33600 Pessac, France
| | - Daniel Taton
- University of Bordeaux, LCPO, UMR 5629, F-33600 Pessac, France
- CNRS, LCPO, UMR 5629, F-33600 Pessac, France
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19
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Miyamae N, Watanabe N, Moritaka M, Nakano K, Ichikawa Y, Kotsuki H. Asymmetric organocatalytic desymmetrization of 4,4-disubstituted cyclohexadienones at high pressure: a new powerful strategy for the synthesis of highly congested chiral cyclohexenones. Org Biomol Chem 2014; 12:5847-55. [DOI: 10.1039/c4ob00733f] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A highly diastereoselective and enantioselective method for the asymmetric desymmetrization of 4,4-disubstituted cyclohexadienones at high pressure was developed.
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Affiliation(s)
- Naomu Miyamae
- Laboratory of Natural Products Chemistry
- Faculty of Science
- Kochi University
- Kochi 780-8520, Japan
| | - Naruhisa Watanabe
- Laboratory of Natural Products Chemistry
- Faculty of Science
- Kochi University
- Kochi 780-8520, Japan
| | - Maya Moritaka
- Laboratory of Natural Products Chemistry
- Faculty of Science
- Kochi University
- Kochi 780-8520, Japan
| | - Keiji Nakano
- Laboratory of Natural Products Chemistry
- Faculty of Science
- Kochi University
- Kochi 780-8520, Japan
| | - Yoshiyasu Ichikawa
- Laboratory of Natural Products Chemistry
- Faculty of Science
- Kochi University
- Kochi 780-8520, Japan
| | - Hiyoshizo Kotsuki
- Laboratory of Natural Products Chemistry
- Faculty of Science
- Kochi University
- Kochi 780-8520, Japan
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20
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Zeng C, Zheng C, Zhao J, Zhao G. Divergent total syntheses of (-)-lycopladine D, (+)-fawcettidine, and (+)-lycoposerramine Q. Org Lett 2013; 15:5846-9. [PMID: 24188014 DOI: 10.1021/ol402906y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enantioselective total syntheses of (+)-fawcettidine and (+)-lycoposerramine Q as well as the first total synthesis of (-)-lycopladine D from a common intermediate have been accomplished by a divergent path. The common intermediate was derived from a Hajos-Parrish-like diketone by a stereoselective Birch reduction and a Suzuki coupling. The synthesis of (-)-lycopladine D featured an allylic oxidation and a biomimetic aminoketalization while the route to (+)-fawcettidine and (+)-lycoposerramine Q highlighted an oxidative rearrangement.
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Affiliation(s)
- Chen Zeng
- Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China
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21
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Liautard V, Jardel D, Davies C, Berlande M, Buffeteau T, Cavagnat D, Robert F, Vincent JM, Landais Y. Organocatalyzed Aldol Reaction between Pyridine-2-carbaldehydes and α-Ketoacids: A Straightforward Route towards Indolizidines and Isotetronic Acids. Chemistry 2013; 19:14532-9. [DOI: 10.1002/chem.201302264] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Indexed: 11/08/2022]
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22
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Trzoss L, Xu J, Lacoske MH, Theodorakis EA. Synthesis of the tetracyclic core of Illicium sesquiterpenes using an organocatalyzed asymmetric Robinson annulation. Beilstein J Org Chem 2013; 9:1135-40. [PMID: 23843905 PMCID: PMC3701413 DOI: 10.3762/bjoc.9.126] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/24/2013] [Indexed: 01/19/2023] Open
Abstract
An enantioselective synthesis of the core framework of neurotrophic Illicium majucin-type sesquiterpenes is described here. This strategy is based on an organocatalyzed asymmetric Robinson annulation and provides an efficient approach for a diversity-oriented synthesis of Illicium natural products that holds remarkable therapeutic potential for neurodegenerative diseases.
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Affiliation(s)
- Lynnie Trzoss
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA
| | - Jing Xu
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA
| | - Michelle H Lacoske
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA
| | - Emmanuel A Theodorakis
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA
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23
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Gratzer K, Gururaja GN, Waser M. Towards Tartaric-Acid-Derived Asymmetric Organocatalysts. European J Org Chem 2013; 2013:4471-4482. [PMID: 24194674 PMCID: PMC3806311 DOI: 10.1002/ejoc.201201675] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Indexed: 11/22/2022]
Abstract
Tartaric acid is one of the most prominent naturally occurring chiral compounds. Whereas its application in the production of chiral ligands for metal-catalysed reactions has been exhaustively investigated, its potential to provide new organocatalysts has been less extensively explored. Nevertheless, some impressive results, such as the use of TADDOLs as chiral H-bonding catalysts or of tartrate-derived asymmetric quaternary ammonium salt catalysts, have been reported over the last decade. The goal of this article is to provide a representative overview of the potential and the limitations of tartaric acid or TADDOLs in the creation of new organocatalysts and to highlight some of the most spectacular applications of these catalysts, as well as to summarize case studies in which other classes of chiral backbones were better suited.
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Affiliation(s)
- Katharina Gratzer
- Institute of Organic Chemistry, Johannes Kepler University Linz Altenbergerstraße 69, 4040 Linz, Austria, http://www.orc.jku.at/mwaser
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Novel supported and unsupported prolinamides as organocatalysts for enantioselective cyclization of triketones. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.03.123] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Trzoss L, Xu J, Lacoske MH, Mobley WC, Theodorakis EA. Illicium sesquiterpenes: divergent synthetic strategy and neurotrophic activity studies. Chemistry 2013; 19:6398-408. [PMID: 23526661 PMCID: PMC3875175 DOI: 10.1002/chem.201300198] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Indexed: 01/12/2023]
Abstract
Majucin-type sesquiterpenes from Illicium sp., such as jiadifenolide (2), jiadifenin (3), and (1R,10S)-2-oxo-3,4-dehydroxyneomajucin (4, ODNM), possess a complex caged chemical architecture and remarkable neurotrophic activities. As such, they represent attractive small-molecule leads against various neurodegenerative diseases. We present an efficient, enantioselective, and unified synthesis of 2, 3, and 4 and designed analogues that diverge from tetracyclic key intermediate 7. The synthesis of 7 is highlighted by the use of an enantioselective Robinson annulation reaction (construction of the AB rings), a Pd-mediated carbomethoxylation reaction (construction of the C ring), and a one-pot oxidative reaction cascade (construction of the D ring). Evaluation of the neurotrophic activity of these compounds led to the identification of several highly potent small molecules that significantly enhanced the activity of nerve growth factor (NGF) in PC-12 cells. Moreover, efforts to define the common pharmacophoric motif suggest that substitution at the C-10 center significantly affects bioactivity, while the hemiketal moiety of 2 and 3 and the C-1 substitution might not be critical to the neurotrophic activity.
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Affiliation(s)
- Lynnie Trzoss
- Department of Chemistry and Biochemistry, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA, Fax: (+)1-858-822-0386
| | - Jing Xu
- Department of Chemistry and Biochemistry, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA, Fax: (+)1-858-822-0386
| | - Michelle H. Lacoske
- Department of Chemistry and Biochemistry, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA, Fax: (+)1-858-822-0386
| | - William C. Mobley
- Department of Neurosciences, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0752, USA
| | - Emmanuel A. Theodorakis
- Department of Chemistry and Biochemistry, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA, Fax: (+)1-858-822-0386
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Fan X, Sayalero S, Pericàs MA. Asymmetric α-Amination of Aldehydes Catalyzed by PS-Diphenylprolinol Silyl Ethers: Remediation of Catalyst Deactivation for Continuous Flow Operation. Adv Synth Catal 2012. [DOI: 10.1002/adsc.201200887] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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28
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Beniazza R, Desvergnes V, Girard E, Kauffmann B, Berlande M, Landais Y. Development of domino processes by using 7-silylcycloheptatrienes and its analogues. Chemistry 2012; 18:11976-86. [PMID: 22926782 DOI: 10.1002/chem.201201527] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Indexed: 11/12/2022]
Abstract
7-Silyl- and 7-silylmethylcycloheptatrienes were shown to react with acylnitroso reagents at room temperature, through their norcaradiene forms, to generate the corresponding cycloadducts 5 a-b and 6 a-b as single diastereomers. The course of the reaction was dramatically modified by changing the reaction conditions. Using a polar medium, functionalized cyclohexa-1,3-dienes 7 a-b and bicyclic compounds 13 a-b were instead generated, incorporating one or two amino groups. Similar behavior was observed by using other dienophiles, including triazolinedione, but also activated aldehydes and ketones. A tentative mechanism has been proposed to rationalize the formation of both classes of products that relies on a domino process involving four consecutive elementary steps, in this order: 1) electrocyclic process, 2) hetero-Diels-Alder reaction, 3) cyclopropane ring opening, and 4) hetero-Diels-Alder reaction. Trapping of the cationic intermediate and isolation of the primary cycloadduct provide support for this hypothesis. An enantioselective version of the cascade using cycloheptatriene 4 b and aldehydes and ketones, under copper(II) catalysis was also carried out, leading to cyclohexa-1,3-dienes 21, 28, and 30 with enantioselectivities up to 93 % ee. Finally, elaboration of the intermediates above has been carried out, opening a straightforward access to sugar mimics 42-43 and complex polycyclic systems 36 and 39.
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Affiliation(s)
- Redouane Beniazza
- Université de Bordeaux, Institut des Sciences Moléculaires, UMR-CNRS 5255, 351, cours de la libération, 33405 Talence Cedex, France
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29
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Magnus P, Brozell AJ. Lewis Acid Catalyzed α-Functionalization of Ketals for the Regioselective Synthesis of α-Carbamoyl Ketals. Org Lett 2012; 14:3952-4. [DOI: 10.1021/ol301710w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Philip Magnus
- Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712-1167, United States
| | - Alec J. Brozell
- Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712-1167, United States
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30
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Trzoss L, Xu J, Lacoske MH, Mobley WC, Theodorakis EA. Enantioselective synthesis of (-)-jiadifenin, a potent neurotrophic modulator. Org Lett 2011; 13:4554-7. [PMID: 21812392 DOI: 10.1021/ol201742j] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first enantioselective synthesis of (-)-jiadifenin (1), a potent neurite outgrowth promoter isolated from the Illicium species, is described. The synthetic strategy builds upon bicyclic motif 6, which represents the AB ring of the natural product and proceeds in 19 steps and 1.1% overall yield. Key to our approach is a Mn(III)-mediated oxidation reaction of A ring that, following a regio- and diastereoselective α-hydroxylation and methylation sequence, produces the desired functionalities of (-)-jiadifenin. The effect of synthetic 1 in NGF-mediated neurite outgrowth was also measured in PC-12 cells.
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Affiliation(s)
- Lynnie Trzoss
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, USA
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31
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Abstract
The strategic use of thiopyran templates to facilitate polypropionate synthesis was first demonstrated in Woodward's landmark total synthesis of erythromycin A in 1981 where the topology of a fused bicyclic system was exploited. In the ensuing three decades, various alternative strategic applications of thiopyran motifs to achieve key stereoselective transformations have emerged including, inter alia, unique substrates for chemoenzymatic syntheses, surrogates for 3-pentanone in enantioselective aldol reactions, and templates for enantiotopic group selective reactions. This review summarizes these developments.
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Affiliation(s)
- Dale E Ward
- Department of Chemistry, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada.
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32
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Beattie C, North M, Villuendas P. Proline-catalysed amination reactions in cyclic carbonate solvents. Molecules 2011; 16:3420-32. [PMID: 21512450 PMCID: PMC6260617 DOI: 10.3390/molecules16043420] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 04/19/2011] [Accepted: 04/20/2011] [Indexed: 11/24/2022] Open
Abstract
Propylene carbonate is shown to be an environmentally friendly and sustainable replacement for dichloromethane and acetonitrile in proline-catalysed α-hydrazinations of aldehydes and ketones. Enantioselectivities comparable to those obtained in conventional solvents or ionic liquids can be obtained, even when using a lower catalyst loading.
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Affiliation(s)
| | - Michael North
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +44-191-222-7128; Fax: +44-191-222-6929
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Xu J, Trzoss L, Chang WK, Theodorakis EA. Enantioselective total synthesis of (-)-jiadifenolide. Angew Chem Int Ed Engl 2011; 50:3672-6. [PMID: 21400650 DOI: 10.1002/anie.201100313] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Indexed: 11/07/2022]
Affiliation(s)
- Jing Xu
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0358, USA
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34
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Xu J, Trzoss L, Chang WK, Theodorakis EA. Enantioselective Total Synthesis of (−)-Jiadifenolide. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201100313] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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35
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Fuentes de Arriba ÁL, Seisdedos DG, Simón L, Alcázar V, Raposo C, Morán JR. Synthesis of Monoacylated Derivatives of 1,2- Cyclohexanediamine. Evaluation of their Catalytic Activity in the Preparation of Wieland−Miescher Ketone. J Org Chem 2010; 75:8303-6. [DOI: 10.1021/jo101723v] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - David G. Seisdedos
- Organic Chemistry Department, Plaza de los Caídos 1-5, Universidad de Salamanca, Salamanca 37008, Spain
| | - Luis Simón
- Organic Chemistry Department, Plaza de los Caídos 1-5, Universidad de Salamanca, Salamanca 37008, Spain
| | - Victoria Alcázar
- Industrial Chemistry and Environmental Engineering Department, José Gutiérrez Abascal 2, Universidad Politécnica de Madrid, Madrid 28006, Spain
| | - César Raposo
- Mass Spectrometry Service, Plaza de los Caídos, 1-5, Universidad de Salamanca, Salamanca 37008, Spain
| | - Joaquín R. Morán
- Organic Chemistry Department, Plaza de los Caídos 1-5, Universidad de Salamanca, Salamanca 37008, Spain
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36
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Fuentes de Arriba AL, Simón L, Raposo C, Alcázar V, Sanz F, Muñiz FM, Morán JR. Imidazolidinone intermediates in prolinamide-catalyzed aldol reactions. Org Biomol Chem 2010; 8:2979-85. [PMID: 20461270 DOI: 10.1039/b926284a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between acetone and 4-nitrobenzaldehyde catalyzed by aniline prolinamide 1 was studied in depth. Working in different solvents with equimolar amounts of reagents and monitoring the reaction by 1H NMR, we detected and identified several imidazolidinones, such as those of the acetone 4, the aldol products 5a and 5b, and aldehydes 10a and 10b. According to our results, these compounds could influence the reaction rate and diminish product enantioselectivity. Furthermore, acetone imidazolidinone 4 was seen to react with 4-nitrobenzaldehyde to furnish the aldol product 3. This reaction can be catalyzed by different nucleophiles and acids. In fact, strong acids such as camphorsulfonic or trifluoroacetic acid, convert imidazolidinones into iminium salts and afford more enantioselective aldol reactions when different aromatic prolinamides are used. Enantiomeric excesses of ca. 82% are reached.
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Affiliation(s)
- Angel L Fuentes de Arriba
- Departamento de Química Orgánica, Universidad de Salamanca, Plaza de los Caídos 1-5, E-37008, Salamanca, Spain
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37
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Organocatalyzed asymmetric alpha-oxidation, alpha-aminoxylation and alpha-amination of carbonyl compounds. Molecules 2010; 15:917-58. [PMID: 20335955 PMCID: PMC6263195 DOI: 10.3390/molecules15020917] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2009] [Revised: 01/27/2010] [Accepted: 02/05/2010] [Indexed: 11/17/2022] Open
Abstract
Organocatalytic asymmetric α-oxidation and amination reactions of carbonyl compounds are highly useful synthetic methodologies, especially in generating chiral building blocks that previously have not been easily accessible by traditional methods. The concept is relatively new and therefore the list of new catalysts, oxidizing and aminating reagents, as well as new substrates, are expanding at an amazing rate. The scope of this review includes new reactions and catalysts, mechanistic aspects and synthetic applications of α-oxidation, hydroxylation, aminoxylation, amination, hydrazination, hydroxyamination and related α-heteroatom functionalization of aldehydes, ketones and related active methylene compounds published during 2005–2009.
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Inomata K, Akahane Y, Endo Y. Asymmetric Intramolecular Aldol Reaction Mediated by (S)-N-Substituted-N-(2-pyrrolidinylmethyl)amine to Prepare Wieland-Miescher Ketone. HETEROCYCLES 2010. [DOI: 10.3987/com-10-s(e)119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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39
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Mori K, Katoh T, Suzuki T, Noji T, Yamanaka M, Akiyama T. Chiral Phosphoric Acid Catalyzed Desymmetrization of meso-1,3-Diones: Asymmetric Synthesis of Chiral Cyclohexenones. Angew Chem Int Ed Engl 2009; 48:9652-4. [DOI: 10.1002/anie.200905271] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Mori K, Katoh T, Suzuki T, Noji T, Yamanaka M, Akiyama T. Chiral Phosphoric Acid Catalyzed Desymmetrization of meso-1,3-Diones: Asymmetric Synthesis of Chiral Cyclohexenones. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200905271] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Bradshaw B, Etxebarría-Jardi G, Bonjoch J, Viózquez S, Guillena G, Nájera C. Efficient Solvent-Free Robinson Annulation Protocols for the Highly Enantioselective Synthesis of the Wieland-Miescher Ketone and Analogues. Adv Synth Catal 2009. [DOI: 10.1002/adsc.200900321] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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42
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Akiyama T, Katoh T, Mori K. Enantioselective Robinson-Type Annulation Reaction Catalyzed by Chiral Phosphoric Acids. Angew Chem Int Ed Engl 2009; 48:4226-8. [DOI: 10.1002/anie.200901127] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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43
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Akiyama T, Katoh T, Mori K. Enantioselective Robinson-Type Annulation Reaction Catalyzed by Chiral Phosphoric Acids. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200901127] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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45
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Inomata K, Akahane Y, Endo Y. A New Chiral Synthesis of Wieland-Miescher Ketone Catalyzed by a Combination of (S)-N-Benzyl-N-(2-pyrrolidinylmethyl)amine Derivative and Brønsted Acid. HETEROCYCLES 2009. [DOI: 10.3987/com-08-s(f)86] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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46
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Chen F, Huang S, Zhang H, Liu F, Peng Y. Proline-based dipeptides with two amide units as organocatalyst for the asymmetric aldol reaction of cyclohexanone with aldehydes. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.07.051] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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47
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Kennedy JWJ, Vietrich S, Weinmann H, Brittain DEA. Synthesis of 7a-Substituted Hajos−Wiechert Ketone Analogues. J Org Chem 2008; 73:5151-4. [DOI: 10.1021/jo800638s] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Sophia Vietrich
- Medicinal Chemistry, Bayer Schering Pharma AG, 13342 Berlin, Germany
| | - Hilmar Weinmann
- Medicinal Chemistry, Bayer Schering Pharma AG, 13342 Berlin, Germany
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48
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Ramachary DB, Reddy YV, Kishor M. Multi-catalysis reactions: direct organocatalytic sequential one-pot synthesis of highly functionalized cyclopenta[b]chromen-1-ones. Org Biomol Chem 2008; 6:4188-97. [DOI: 10.1039/b812551a] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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49
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50
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Inomata K, Nagamine T, Endo Y. A New Chiral Synthesis of a Bicyclic Enedione Containing a Seven-Membered Ring Mediated by a Combination of Chiral Amine and Brønsted Acid. HETEROCYCLES 2008. [DOI: 10.3987/com-08-s(n)81] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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