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Zhu HT, Liang CM, Li TY, Li LY, Zhang RL, Wang JN, Qi RQ, Zhang JM, Yang RH, Yang YQ, Zhou AX, Jin X, Zhou NN. Dual Proton/Silver-Catalyzed Serial (5 + 2)-Cycloaddition and Nazarov Cyclization of ( E)-2-Arylidene-3-hydroxyindanones with Conjugated Eneynes: Synthesis of Indanone-Fused Benzo[ cd]azulenes. J Org Chem 2023; 88:3409-3423. [PMID: 36847758 DOI: 10.1021/acs.joc.2c02247] [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
A one-pot step-economic tandem process involving (5 + 2)-cycloaddition and Nazarov cyclization reactions has been reported for the facile synthesis of indanone-fused benzo[cd]azulenes from (E)-2-arylidene-3-hydroxyindanones and conjugated eneynes. This highly regio- and stereoselective bisannulation reaction is enabled by dual silver and Brønsted acid catalysis and opens up a new avenue for the construction of important bicyclo[5.3.0]decane skeletons.
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Affiliation(s)
- Hai-Tao Zhu
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Chun-Miao Liang
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Ting-Yan Li
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Lin-Yan Li
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Rui-Ling Zhang
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Jun-Na Wang
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Rui-Qing Qi
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Jia-Min Zhang
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Ruo-Han Yang
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - Yin-Qi Yang
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
| | - An-Xi Zhou
- Key Laboratory of Applied Organic Chemistry, Higher Institutions of Jiangxi Province, Shangrao Normal University, Shangrao 334000, China
| | - Xiaojie Jin
- Gansu University Key Laboratory for Molecular Medicine & Chinese Medicine Prevention and Treatment of Major Diseases, Gansu University of Chinese Medicine, Lanzhou 730000, China
| | - Ni-Ni Zhou
- College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji 721013, China
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2
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Truax NJ, Ayinde S, Liu JO, Romo D. Total Synthesis of Rameswaralide Utilizing a Pharmacophore-Directed Retrosynthetic Strategy. J Am Chem Soc 2022; 144:18575-18585. [PMID: 36166374 DOI: 10.1021/jacs.2c08245] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A pharmacophore-directed retrosynthetic strategy was applied to the first total synthesis of the cembranoid rameswaralide in order to simultaneously achieve a total synthesis while also developing a structure-activity relationship profile throughout the synthetic effort. The synthesis utilized a Diels-Alder lactonization process, including a rare kinetic resolution to demonstrate the potential of this strategy for an enantioselective synthesis providing both the 5,5,6- and, through a ring expansion, 5,5,7-tricyclic ring systems present in several Sinularia soft coral cembranoids. A pivotal synthetic intermediate, a tricyclic epoxy α-bromo cycloheptenone, displayed high cytotoxicity with interesting selectivity toward the HCT-116 colon cancer cell line. This intermediate enabled the pursuit of three unique D-ring annulation strategies including a photocatalyzed intramolecular Giese-type radical cyclization and a diastereoselective, intramolecular enamine-mediated Michael addition, with the latter annulation constructing the final D-ring to deliver rameswaralide. The serendipitous discovery of an oxidation state transposition of the tricyclic epoxy cycloheptenone proceeding through a presumed doubly vinylogous, E1-type elimination enabled the facile introduction of the required α-methylene butyrolactone. Preliminary biological tests of rameswaralide and precursors demonstrated weak cytotoxicity; however, the comparable cytotoxicity of a simple 6,7-bicyclic β-keto ester, corresponding to the CD-ring system of rameswaralide, to that of the natural product itself suggests that such bicyclic β-ketoesters may constitute an interesting pharmacophore that warrants further exploration.
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Affiliation(s)
- Nathanyal J Truax
- Department of Chemistry & Biochemistry, Baylor University, 101 Bagby Avenue, Waco, Texas 76710, United States
| | - Safiat Ayinde
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, 725 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Jun O Liu
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, 725 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Daniel Romo
- Department of Chemistry & Biochemistry, Baylor University, 101 Bagby Avenue, Waco, Texas 76710, United States
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3
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Doerksen RS, Hodík T, Hu G, Huynh NO, Shuler WG, Krische MJ. Ruthenium-Catalyzed Cycloadditions to Form Five-, Six-, and Seven-Membered Rings. Chem Rev 2021; 121:4045-4083. [PMID: 33576620 DOI: 10.1021/acs.chemrev.0c01133] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ruthenium-catalyzed cycloadditions to form five-, six-, and seven-membered rings are summarized, including applications in natural product total synthesis. Content is organized by ring size and reaction type. Coverage is limited to processes that involve formation of at least one C-C bond. Processes that are stoichiometric in ruthenium or exploit ruthenium as a Lewis acid (without intervention of organometallic intermediates), ring formations that occur through dehydrogenative condensation-reduction, σ-bond activation-initiated annulations that do not result in net reduction of bond multiplicity, and photochemically promoted ruthenium-catalyzed cycloadditions are not covered.
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Affiliation(s)
- Rosalie S Doerksen
- Department of Chemistry, University of Texas at Austin,, Welch Hall (A5300), 105 East 24th Street, Austin, Texas 78712, United States
| | - Tomáš Hodík
- Department of Chemistry, University of Texas at Austin,, Welch Hall (A5300), 105 East 24th Street, Austin, Texas 78712, United States
| | - Guanyu Hu
- Department of Chemistry, University of Texas at Austin,, Welch Hall (A5300), 105 East 24th Street, Austin, Texas 78712, United States
| | - Nancy O Huynh
- Department of Chemistry, University of Texas at Austin,, Welch Hall (A5300), 105 East 24th Street, Austin, Texas 78712, United States
| | - William G Shuler
- Department of Chemistry, University of Texas at Austin,, Welch Hall (A5300), 105 East 24th Street, Austin, Texas 78712, United States
| | - Michael J Krische
- Department of Chemistry, University of Texas at Austin,, Welch Hall (A5300), 105 East 24th Street, Austin, Texas 78712, United States
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4
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Abstract
Covering: 1986 to 2020Natural products are an enduring source of chemical information useful for probing biologically relevant chemical space. Toward gathering further structure-activity relationship (SAR) information for a particular natural product, synthetic chemists traditionally proceeded first by a total synthesis effort followed by the synthesis of simplified derivatives. While this approach has proven fruitful, it often does not incorporate hypotheses regarding structural features necessary for bioactivity at the synthetic planning stage, but rather focuses on the rapid assembly of the targeted natural product; a goal that often supersedes the opportunity to gather SAR information en route to the natural product. Furthermore, access to simplified variants of a natural product possessing only the proposed essential structural features necessary for bioactivity, typically at lower oxidation states overall, is sometimes non-trivial from the original established synthetic route. In recent years, several synthetic design strategies were described to streamline the process of finding bioactive molecules in concert with fathering further SAR studies for targeted natural products. This review article will briefly discuss traditional retrosynthetic strategies and contrast them to selected examples of recent synthetic strategies for the investigation of biologically relevant chemical space revealed by natural products. These strategies include: diversity-oriented synthesis (DOS), biology-oriented synthesis (BIOS), diverted-total synthesis (DTS), analogue-oriented synthesis (AOS), two-phase synthesis, function-oriented synthesis (FOS), and computed affinity/dynamically ordered retrosynthesis (CANDOR). Finally, a description of pharmacophore-directed retrosynthesis (PDR) developed in our laboratory and initial applications will be presented that was initially inspired by a retrospective analysis of our synthetic route to pateamine A completed in 1998.
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Affiliation(s)
- Nathanyal J Truax
- Department of Chemistry & Biochemistry, Baylor University, Waco, Texas 76710, USA.
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5
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Sasaki I, Ohmura T, Suginome M. Construction of Silicon-Containing Seven-Membered Rings by Catalytic [4 + 2 + 1] Cycloaddition through Rhodium Silylenoid. Org Lett 2020; 22:2961-2966. [DOI: 10.1021/acs.orglett.0c00690] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Ikuo Sasaki
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Toshimichi Ohmura
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Michinori Suginome
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
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6
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Truax NJ, Ayinde S, Van K, Liu JO, Romo D. Pharmacophore-Directed Retrosynthesis Applied to Rameswaralide: Synthesis and Bioactivity of Sinularia Natural Product Tricyclic Cores. Org Lett 2019; 21:7394-7399. [PMID: 31498642 DOI: 10.1021/acs.orglett.9b02713] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A pharmacophore-directed retrosynthesis strategy applied to rameswaralide provided simplified precursors bearing the common 5,5,6 (red) and 5,5,7 (blue) skeleton present in several cembranoid and norcembranoids from Sinularia soft corals. Key steps include a Diels-Alder lactonization organocascade delivering the common 5,5,6 core and a subsequent ring expansion affording a 5,5,7 core serviceable for the synthesis of rameswaralide. Initial structure-activity relationships of intermediates en route to the natural product have revealed interesting differential and selective cytotoxicity.
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Affiliation(s)
- Nathanyal J Truax
- Department of Chemistry & Biochemistry , Baylor University , Waco , Texas 76710 , United States
| | - Safiat Ayinde
- Department of Pharmacology and Molecular Sciences , John Hopkins School of Medicine , 725 North Wolfe Street , Baltimore , Maryland 21205 , United States
| | - Khoi Van
- Department of Chemistry & Biochemistry , Baylor University , Waco , Texas 76710 , United States
| | - Jun O Liu
- Department of Pharmacology and Molecular Sciences , John Hopkins School of Medicine , 725 North Wolfe Street , Baltimore , Maryland 21205 , United States
| | - Daniel Romo
- Department of Chemistry & Biochemistry , Baylor University , Waco , Texas 76710 , United States
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7
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Mbaezue II, Ylijoki KEO. [5 + 1 + 2 + 1] vs [5 + 1 + 1 + 2] Rhodium-Catalyzed Cycloaddition Reactions of Vinylcyclopropanes with Terminal Alkynes and Carbon Monoxide: Density Functional Theory Investigations of Convergent Mechanistic Pathways and Reaction Regioselectivity. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00323] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ifenna I. Mbaezue
- Department of Chemistry, Saint Mary’s University, Halifax, Nova Scotia, Canada B3H 3C3
| | - Kai E. O. Ylijoki
- Department of Chemistry, Saint Mary’s University, Halifax, Nova Scotia, Canada B3H 3C3
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8
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Craig RA, Stoltz BM. Polycyclic Furanobutenolide-Derived Cembranoid and Norcembranoid Natural Products: Biosynthetic Connections and Synthetic Efforts. Chem Rev 2017; 117:7878-7909. [PMID: 28520418 PMCID: PMC5497599 DOI: 10.1021/acs.chemrev.7b00083] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The polycyclic furanobutenolide-derived cembranoid and norcembranoid natural products are a family of congested, stereochemically complex, and extensively oxygenated polycyclic diterpenes and norditerpenes. Although the elegant architectures and biological activity profiles of these natural products have captured the attention of chemists since the isolation of the first members of the family in the 1990s, the de novo synthesis of only a single polycyclic furanobutenolide-derived cembranoid and norcembranoid has been accomplished. This article begins with a brief discussion of the proposed biosyntheses and biosynthetic connections among the polycyclic furanobutenolide-derived cembranoids and norcembranoids and then provides a comprehensive review of the synthetic efforts toward each member of the natural product family, including biomimetic, semisynthetic, and de novo synthetic strategies. This body of knowledge has been gathered to provide insight into the reactivity and constraints of these compact and highly oxygenated polycyclic structures, as well as to offer guidance for future synthetic endeavors.
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Affiliation(s)
- Robert A. Craig
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Brian M. Stoltz
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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9
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Shu XZ, Schienebeck CM, Li X, Zhou X, Song W, Chen L, Guzei IA, Tang W. Rhodium-Catalyzed Stereoselective Intramolecular [5 + 2] Cycloaddition of 3-Acyloxy 1,4-Enyne and Alkene. Org Lett 2015; 17:5128-31. [PMID: 26440751 DOI: 10.1021/acs.orglett.5b02665] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first rhodium-catalyzed intramolecular [5 + 2] cycloaddition of 3-acyloxy 1,4-enyne and alkene was developed. The cycloaddition is highly diastereoselective in most cases. Various cis-fused bicyclo[5.3.0]decadienes were prepared stereoselectively. The chirality in the propargylic ester starting materials could be transferred to the bicyclic products with high efficiency. Electron-deficient phosphine ligand greatly facilitated the cycloaddition. Up to three new stereogenic centers could be generated. The resulting diene in the products could be hydrolyzed to enones, which allowed the introduction of more functional groups to the seven-membered ring.
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Affiliation(s)
- Xing-zhong Shu
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Casi M Schienebeck
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Xiaoxun Li
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Xin Zhou
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Wangze Song
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Lianqing Chen
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Ilia A Guzei
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Weiping Tang
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States.,Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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10
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Nguyen TAD, Wright AM, Page JS, Wu G, Hayton TW. Oxidation of Alcohols and Activated Alkanes with Lewis Acid-Activated TEMPO. Inorg Chem 2014; 53:11377-87. [DOI: 10.1021/ic5018888] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Thuy-Ai D. Nguyen
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Ashley M. Wright
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Joshua S. Page
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Guang Wu
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Trevor W. Hayton
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
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11
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Li Y, Palframan MJ, Pattenden G, Winne JM. A strategy towards the synthesis of plumarellide based on biosynthesis speculation, featuring a transannular 4+2 type cyclisation from a cembranoid furanoxonium ion intermediate. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.06.090] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Schienebeck CM, Li X, Shu XZ, Tang W. 3-Acyloxy-1,4-enyne: a New Five-carbon Synthon for Rhodium-Catalyzed (5+2) Cycloadditions. PURE APPL CHEM 2014; 86:409-417. [PMID: 24839310 DOI: 10.1515/pac-2014-5042] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Seven-membered rings are ubiquitous in natural products and pharmaceutical agents and their syntheses continue to stimulate the development of novel synthetic methods. The (5+2) cycloaddition is one of the most efficient ways to access seven-membered rings since the 2-carbon components (alkenes, alkynes, or allenes) are readily available. Prior to our study, however, there was only one type of transition metal-catalyzed (5+2) cycloaddition: the reaction between vinylcyclopropanes and alkenes, alkynes, or allenes. We recently developed a new type of transition metal-catalyzed (5+2) cycloaddition, where the 5-carbon building block is 3-acyloxy-1,4-enyne (ACE). Our recent progress on Rh-catalyzed intra- and intermolecular (5+2) cycloadditions of ACEs and alkynes is summarized in this article. Using chiral propargylic esters, bicyclic products were prepared in high optical purity by the intramolecular (5+2) cycloadditions. Monocyclic seven-membered rings were synthesized by intermolecular (5+2) cycloaddition of ACEs and alkynes. Kinetic studies indicated that the rate of this intermolecular cycloaddition was significantly accelerated when the acetate was replaced by dimethylaminobenzoate. DFT calculations suggested that novel metallacycles were generated by a Rh-promoted oxidative cycloaddition of 1,4-enynes accompanied by a 1,2-acyloxy migration of propargylic esters.
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Affiliation(s)
- Casi M Schienebeck
- School of Pharmacy and Department of Chemistry, University of Wisconsin, Madison, WI 53705, USA
| | - Xiaoxun Li
- School of Pharmacy and Department of Chemistry, University of Wisconsin, Madison, WI 53705, USA
| | - Xing-Zhong Shu
- School of Pharmacy and Department of Chemistry, University of Wisconsin, Madison, WI 53705, USA
| | - Weiping Tang
- School of Pharmacy and Department of Chemistry, University of Wisconsin, Madison, WI 53705, USA
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13
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C–C Bond Formation on Activation of Alkynes and Alkenes with (C5R5)Ru Catalysts. TOP ORGANOMETAL CHEM 2014. [DOI: 10.1007/3418_2014_82] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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14
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Ylijoki KEO, Stryker JM. [5 + 2] Cycloaddition Reactions in Organic and Natural Product Synthesis. Chem Rev 2012; 113:2244-66. [PMID: 23153111 DOI: 10.1021/cr300087g] [Citation(s) in RCA: 310] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Kai E. O. Ylijoki
- Department of Chemistry, University
of Alberta, Edmonton,
Alberta T6G 2G2, Canada
| | - Jeffrey M. Stryker
- Department of Chemistry, University
of Alberta, Edmonton,
Alberta T6G 2G2, Canada
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15
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Shu XZ, Li X, Shu D, Huang S, Schienebeck CM, Zhou X, Robichaux PJ, Tang W. Rhodium-catalyzed intra- and intermolecular [5 + 2] cycloaddition of 3-acyloxy-1,4-enyne and alkyne with concomitant 1,2-acyloxy migration. J Am Chem Soc 2012; 134:5211-21. [PMID: 22364320 DOI: 10.1021/ja2109097] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new type of rhodium-catalyzed [5 + 2] cycloaddition was developed for the synthesis of seven-membered rings with diverse functionalities. The ring formation was accompanied by a 1,2-acyloxy migration event. The five- and two-carbon components of the cycloaddition are 3-acyloxy-1,4-enynes (ACEs) and alkynes, respectively. Cationic rhodium(I) catalysts worked most efficiently for the intramolecular cycloaddition, while only neutral rhodium(I) complexes could facilitate the intermolecular reaction. In both cases, electron-poor phosphite or phosphine ligands often improved the efficiency of the cycloadditions. The scope of ACEs and alkynes was investigated in both the intra- and intermolecular reactions. The resulting seven-membered-ring products have three double bonds that could be selectively functionalized.
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Affiliation(s)
- Xing-Zhong Shu
- School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53705, United States
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16
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Li Y, Pattenden G. Biomimetic syntheses of ineleganolide and sinulochmodin C from 5-episinuleptolide via sequences of transannular Michael reactions. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.09.040] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Biggs-Houck JE, Davis RL, Wei J, Mercado BQ, Olmstead MM, Tantillo DJ, Shaw JT. Carbon–Carbon Bond-Forming Reactions of α-Thioaryl Carbonyl Compounds for the Synthesis of Complex Heterocyclic Molecules. J Org Chem 2011; 77:160-72. [DOI: 10.1021/jo201541e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- James E. Biggs-Houck
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
| | - Rebecca L. Davis
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
| | - Jingqiang Wei
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
| | - Brandon Q. Mercado
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
| | - Marilyn M. Olmstead
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
| | - Dean J. Tantillo
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
| | - Jared T. Shaw
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616,
United States
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18
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Abstract
An approach toward the synthesis of maoecrystal V is described. The synthetic strategy for this approach was designed to address unique challenges posed by the strained tetrahydrofuran ring at the center of the target structure.
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Affiliation(s)
- Zhenhua Gu
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93110, USA
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19
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Li Y, Pattenden G. Perspectives on the structural and biosynthetic interrelationships between oxygenated furanocembranoids and their polycyclic congeners found in corals. Nat Prod Rep 2011; 28:1269-310. [DOI: 10.1039/c1np00023c] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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