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Sun YK, Qiao JB, Xin YM, Zhou Q, Ma ZH, Shao H, Zhao YM. Total Synthesis of Metaphanine and Oxoepistephamiersine. Angew Chem Int Ed Engl 2023; 62:e202310917. [PMID: 37602680 DOI: 10.1002/anie.202310917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/20/2023] [Accepted: 08/21/2023] [Indexed: 08/22/2023]
Abstract
Herein, we report a concise and divergent synthesis of the complex hasubanan alkaloids metaphanine and oxoepistephamiersine from commercially available and inexpensive cyclohexanedione monoethylene acetal. Our synthesis features a palladium-catalyzed cascade cyclization reaction to set the tricyclic carbon framework of the desired molecules, a regioselective Baeyer-Villiger oxidation followed by a MeNH2 triggered skeletal reorganization cascade to construct the benzannulated aza[4.4.3]propellane, and a strategically late-stage regio-/diastereoselective oxidative annulation of sp3 C-H bond to form the challenging THF ring system and hemiketal moiety in a single step. In addition, a highly enantioselective alkylation of cyclohexanedione monoethylene acetal paved the way for the asymmetric synthesis of target molecular.
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Affiliation(s)
- Ya-Kui Sun
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
| | - Jin-Bao Qiao
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
| | - Yu-Meng Xin
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
| | - Qin Zhou
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
| | - Zhi-Hua Ma
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
| | - Hui Shao
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
| | - Yu-Ming Zhao
- Key Laboratory of Applied Surface and Colloid Chemistry & School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Ave, Xi'an, 710119, China
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2
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Liu J, Gao S, Miliordos E, Chen M. Asymmetric Syntheses of ( Z)- or ( E)-β,γ-Unsaturated Ketones via Silane-Controlled Enantiodivergent Catalysis. J Am Chem Soc 2023; 145:19542-19553. [PMID: 37639380 PMCID: PMC11144060 DOI: 10.1021/jacs.3c02595] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Cu-catalyzed highly stereoselective and enantiodivergent syntheses of (Z)- or (E)-β,γ-unsaturated ketones from 1,3-butadienyl silanes are developed. The nature of the silyl group of the dienes has a significant impact on the stereo- and enantioselectivity of the reactions. Under the developed catalytic systems, the reactions of acyl fluorides with phenyldiemthylsilyl-substituted 1,3-diene gave (Z)-β,γ-unsaturated ketones bearing an α-tertiary stereogenic center with excellent enantioselectivities and high Z-selectivities, where the reactions with triisopropylsilyl-substituted 1,3-butadiene formed (E)-β,γ-unsaturated ketones with high optical purities and excellent E-selectivities. The products generated from the reactions contain three functional groups with orthogonal chemical reactivities, which can undergo a variety of transformations to afford synthetically valuable intermediates.
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Affiliation(s)
- Jiaming Liu
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
| | - Shang Gao
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, P. R. China
| | - Evangelos Miliordos
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
| | - Ming Chen
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
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3
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Sharma P, Karmakar I, Brahmachari G, Gupta VK. X-Ray Analysis of N'-Acetyl-4-formyl-N'-phenylbenzohydrazide. CRYSTALLOGR REP+ 2022. [DOI: 10.1134/s1063774522070112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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4
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Brahmachari G, Bhowmick A, Karmakar I. Catalyst- and Additive-Free C(sp 3)-H Functionalization of (Thio)barbituric Acids via C-5 Dehydrogenative Aza-Coupling Under Ambient Conditions. ACS OMEGA 2022; 7:30051-30063. [PMID: 36061699 PMCID: PMC9434791 DOI: 10.1021/acsomega.2c03073] [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: 05/17/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
A one-pot room-temperature-based three-component reaction strategy has been accomplished to access a new series of bio-relevant barbituric/2-thiobarbituric acid hydrazones from the reaction between barbituric/2-thiobarbituric acids, primary aromatic amines, and tert-butyl nitrite in an acetonitrile solvent, without the aid of any catalysts/additives. The ambient reaction conditions can efficiently implement the C(sp3)-H functionalization of barbituric/2-thiobarbituric acids via C-5 dehydrogenative aza-coupling. The process does not require column chromatographic purification; pure products are obtained by simple filtration of the resulting reaction mixture, followed by washing the crude residue with distilled water. The catalyst-free ambient reaction conditions, operational simplicity, broad substrate scope and tolerance for various functional groups, no need for chromatographic purification, good to excellent yields of products within reasonable reaction times in minutes, clean reaction profile, and gram-scale synthetic applicability make this procedure attractive, green, and cost-effective.
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5
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St John-Campbell S, Sheppard T. Imine Azaenolates: Synthesis, Reactivity and Outlook. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Tom Sheppard
- University College London UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND
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6
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Grzybowski BA, Badowski T, Molga K, Szymkuć S. Network search algorithms and scoring functions for advanced‐level computerized synthesis planning. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2022. [DOI: 10.1002/wcms.1630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bartosz A. Grzybowski
- Institute of Organic Chemistry, Polish Academy of Sciences Warsaw Poland
- Center for Soft and Living Matter, Institute for Basic Science (IBS) Ulsan Republic of Korea
- Department of Chemistry Ulsan National Institute of Science and Technology (UNIST) Ulsan Republic of Korea
| | - Tomasz Badowski
- Institute of Organic Chemistry, Polish Academy of Sciences Warsaw Poland
| | - Karol Molga
- Institute of Organic Chemistry, Polish Academy of Sciences Warsaw Poland
| | - Sara Szymkuć
- Institute of Organic Chemistry, Polish Academy of Sciences Warsaw Poland
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7
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Wu BB, Xu J, Bian KJ, Gao Q, Wang XS. Enantioselective Synthesis of Secondary β-Trifluoromethyl Alcohols via Catalytic Asymmetric Reductive Trifluoroalkylation and Diastereoselective Reduction. J Am Chem Soc 2022; 144:6543-6550. [PMID: 35378033 DOI: 10.1021/jacs.2c01422] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Fluorinated motifs are frequently encountered in drugs and agrochemicals. Incorporating fluorine-containing motifs in drug candidates for lead optimization in pharmaceutical research and development has emerged as a powerful tool. The construction of molecules that feature a trifluoromethyl (CF3-) group on a stereogenic carbon has accumulated broad research efforts. Unlike its well-explored, biologically active methyl counterpart, asymmetric construction of β-trifluoromethylated alcohols bearing adjacent stereocenters still remains elusive. Through retrosynthetic analysis, we posited that followed by sequential reduction of carbonyl, the initial construction of chiral α-trifluoromethylated ketones could render the desired product in a facile, one-pot fashion. Herein, we developed the first example of nickel-catalyzed asymmtric reductive cross-coupling trifluoroalkylation of acyl chlorides for enantioselective synthesis of diverse α-trifluoromethylated ketones. The one-pot reduction of these α-trifluoromethylated ketones furnished corresponding alcohols bearing β-CF3-substituted stereogenic carbons with excellent diastereoselectivity and complete enantioselective retention. High yields/enantioselectivity, mild conditions, and good functional group compatibility are shown in the system. Utilities of the method are also illustrated by applying asymmetric, late-stage trifluoroalkylation of biologically active complex molecules, revealing tremendous potential for development of CF3-containing chiral drugs.
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Affiliation(s)
- Bing-Bing Wu
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jie Xu
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Kang-Jie Bian
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Qian Gao
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xi-Sheng Wang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
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8
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Matsuzaki H, Takeda N, Yasui M, Okazaki M, Suzuki S, Ueda M. Synthesis of multi-substituted 1,2,4-triazoles utilising the ambiphilic reactivity of hydrazones. Chem Commun (Camb) 2021; 57:12187-12190. [PMID: 34730140 DOI: 10.1039/d1cc05326d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The synthesis of N-alkyl-1H-1,2,4-triazoles from N,N-dialkylhydrazones and nitriles via formal [3+2] cycloaddition including the C-chlorination/nucleophilic addition/cyclisation/dealkylation sequence was developed. This sequential reaction utilising the in situ generation of hydrazonoyl chloride based on the ambiphilic reactivity of hydrazones afforded a variety of multi-substituted N-alkyl-triazoles in high yields. The synthetic utility of multi-substituted triazoles was also demonstrated by further transformations.
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Affiliation(s)
- Haruo Matsuzaki
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Norihiko Takeda
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Motohiro Yasui
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Mayuko Okazaki
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Seishin Suzuki
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
| | - Masafumi Ueda
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
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9
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Liu S, Tanabe Y, Kuriyama S, Sakata K, Nishibayashi Y. Ruthenium- and Copper-Catalyzed Propargylic Substitution Reactions of Propargylic Alcohol Derivatives with Hydrazones. Chemistry 2021; 27:15650-15659. [PMID: 34606139 DOI: 10.1002/chem.202103287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Indexed: 11/12/2022]
Abstract
Ruthenium- and copper-catalyzed propargylic substitution reactions of propargylic alcohol derivatives with N-monosubstituted hydrazones as ambident nucleophiles are achieved in which N-monosubstituted hydrazones exhibit impressive different reactivities depending on different catalytic systems, behaving as carbon-centered nucleophiles to give the corresponding propargylic alkylated products in ruthenium catalysis, or as nitrogen-centered nucleophiles to afford the corresponding propargylic aminated products in copper catalysis. DFT calculations were carried out to investigate the detailed reaction pathways of these two systems. Further transformation of propargylic substituted products affords the corresponding multisubstituted pyrazoles as cyclization products in good to high yields.
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Affiliation(s)
- Shiyao Liu
- Department of Applied Chemistry, School of Engineering, The University of Tokyo Hongo, Bunkyo-ku, Tokyo, Japan
| | - Yoshiaki Tanabe
- Department of Applied Chemistry, School of Engineering, The University of Tokyo Hongo, Bunkyo-ku, Tokyo, Japan
| | - Shogo Kuriyama
- Department of Applied Chemistry, School of Engineering, The University of Tokyo Hongo, Bunkyo-ku, Tokyo, Japan
| | - Ken Sakata
- Faculty of Pharmaceutical Sciences, Toho University Miyama, Funabashi, Chiba, Japan
| | - Yoshiaki Nishibayashi
- Department of Applied Chemistry, School of Engineering, The University of Tokyo Hongo, Bunkyo-ku, Tokyo, Japan
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10
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Evolution in heterodonor P-N, P-S and P-O chiral ligands for preparing efficient catalysts for asymmetric catalysis. From design to applications. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214120] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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11
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Abstract
The asymmetric alkylation of enolates is a particularly versatile method for the construction of α-stereogenic carbonyl motifs, which are ubiquitous in synthetic chemistry. Over the past several decades, the focus has shifted to the development of new catalytic methods that depart from classical stoichiometric stereoinduction strategies (e.g., chiral auxiliaries, chiral alkali metal amide bases, chiral electrophiles, etc.). In this way, the enantioselective alkylation of prochiral enolates greatly improves the step- and redox-economy of this process, in addition to enhancing the scope and selectivity of these reactions. In this review, we summarize the origin and advancement of catalytic enantioselective enolate alkylation methods, with a directed emphasis on the union of prochiral nucleophiles with carbon-centered electrophiles for the construction of α-stereogenic carbonyl derivatives. Hence, the transformative developments for each distinct class of nucleophile (e.g., ketone enolates, ester enolates, amide enolates, etc.) are presented in a modular format to highlight the state-of-the-art methods and current limitations in each area.
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Affiliation(s)
- Timothy B Wright
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario K7L 3N6, Canada
| | - P Andrew Evans
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario K7L 3N6, Canada.,Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan, P. R. of China
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12
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Yoshida M. Organocatalytic Asymmetric α-Allylation and Propargylation of α-Branched Aldehydes with Alkyl Halides. J Org Chem 2021; 86:10921-10927. [PMID: 34264085 DOI: 10.1021/acs.joc.1c01394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enantioselective α-allylation and -propargylation of α-branched aldehydes with alkyl halides was successfully performed using a chiral primary amino acid organocatalyst. This alkylation reaction, involving the generation of a chiral quaternary carbon stereocenter, proceeded smoothly in a mildly basic aqueous solution of potassium hydrogen carbonate to furnish α-allylated or -propargylated aldehydes in a good yield (up to 87%) and high enantioselectivity (up to 96% ee).
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Affiliation(s)
- Masanori Yoshida
- Liberal Arts and Sciences, National Institute of Technology (KOSEN), Asahikawa College Shunkodai 2 jo 2-1-6, Asahikawa, Hokkaido 071-8142, Japan
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13
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Mizota I, Nakamura Y, Mizutani S, Mizukoshi N, Terasawa S, Shimizu M. Highly Selective Synthesis of α-Aminoamide Utilizing an Umpolung Reaction and Characteristics of α-Hydrazonoester. Org Lett 2021; 23:4168-4172. [PMID: 34014099 DOI: 10.1021/acs.orglett.1c01117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An umpolung reaction with α-hydrazonoesters was investigated, and it was found that α-N,N-dialkylaminoamides could be directly synthesized in yields up to 92% via a concomitant rearrangement of dialkylamino groups. As an application, a short synthesis of an inhibitor of glycine type-1-transporter was accomplished via subsequent functional group transformations in 28% overall yield.
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Affiliation(s)
- Isao Mizota
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan
| | - Yusuke Nakamura
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan
| | - Shunsuke Mizutani
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan
| | - Nanami Mizukoshi
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan
| | - Shunya Terasawa
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan
| | - Makoto Shimizu
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University, Tsu, Mie 514-8507, Japan.,School of Energy Science and Engineering College, Nanjing Tech University, Nanjing, Jiangsu 211816, China
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14
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Affiliation(s)
- Sina Witzel
- Organisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - A. Stephen K. Hashmi
- Organisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
- Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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15
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Matsuzaki H, Takeda N, Yasui M, Ito Y, Konishi K, Ueda M. Synthesis of Pyrazoles Utilizing the Ambiphilic Reactivity of Hydrazones. Org Lett 2020; 22:9249-9252. [PMID: 33196204 DOI: 10.1021/acs.orglett.0c03465] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A Brønsted acid-mediated synthesis of pyrazoles from conjugated hydrazones through a β-protonation/nucleophilic addition/cyclization/aromatization sequence was developed. This protocol utilizing the ambiphilic reactivity of hydrazones enables not only self-condensation but also cross-condensation, affording multisubstituted pyrazoles in high yields, with a broad substrate scope. This sequential reaction proceeds under mild conditions via a simple operation. Moreover, the method can be applied to the synthesis of a nonsteroidal anti-inflammatory drug, Lonazolac.
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Affiliation(s)
- Haruo Matsuzaki
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan
| | - Norihiko Takeda
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan
| | - Motohiro Yasui
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan
| | - Yuta Ito
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan
| | - Keiji Konishi
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan
| | - Masafumi Ueda
- Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan
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16
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Fang Z, Qi L, Song J, Ren P, Hou C, Ji S, Wang L, Li W. PhI(OAc)
2
‐Promoted 1,2‐Diaza‐Cope Rearrangement of β,γ‐Unsaturated Hydrazones with Acetate/H
2
O: Access to Diacyl/Acyl
N
‐Allylhydrazines. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zhuo‐Yue Fang
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Lin Qi
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Jin‐Yan Song
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Pei‐Xing Ren
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Cong‐Ying Hou
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Shi‐Chao Ji
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Li‐Jing Wang
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
- Key Laboratory of Medicinal Chemistry, and Molecular Diagnosis of the Ministry of Education Key Laboratory of Chemical Biology of Hebei Province Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
| | - Wei Li
- College of Chemistry & Environmental Science Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
- Key Laboratory of Medicinal Chemistry, and Molecular Diagnosis of the Ministry of Education Key Laboratory of Chemical Biology of Hebei Province Hebei University 180 Wusi Donglu 071002 Baoding P. R. China
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17
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Metallinos C, Tran N, Cadwallader D. Diastereoselective Synthesis of Alkylated 1,4-Cyclohexadiene Esters Using Epimeric Pyrroloimidazolones. SYNTHESIS-STUTTGART 2020. [DOI: 10.1055/s-0040-1707351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A pair of ortho-benzoate esters containing epimeric pyrroloimidazolones undergo sequential Birch reduction and diastereoselective alkylation to provide products ranging from 88:12 to >95:5 diastereomeric ratio (dr) for the syn-epimer, and 50:50 to 95:5 dr for the anti-epimer. The stereochemistry of the products is confirmed by a combination of X-ray crystallography on a key anti-epimer-derived product, in combination with specific rotation measurements of enantiomers that are prepared from the syn or anti starting materials. A diastereomerically pure allyl-substituted substrate is shown to undergo Cope rearrangement, which transposes the quaternary chiral center to a remote position without racemization. This work is complementary to asymmetric reductive alkylation reported previously by Schultz using anisole substrates with chiral benzamide auxiliaries in that the pyrroloimidazolones act as surrogates for the methoxy group.
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18
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Wu Z, Liu C, Zhang Z, Zheng R, Zheng Y. Amidase as a versatile tool in amide-bond cleavage: From molecular features to biotechnological applications. Biotechnol Adv 2020; 43:107574. [PMID: 32512219 DOI: 10.1016/j.biotechadv.2020.107574] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 12/27/2022]
Abstract
Amidases (EC 3. 5. 1. X) are versatile biocatalysts for synthesis of chiral carboxylic acids, α-amino acids and amides due to their hydrolytic and acyl transfer activity towards the C-N linkages. They have been extensively exploited and studied during the past years for their high specific activity and excellent enantioselectivity involved in various biotechnological applications in pharmaceutical and agrochemical industries. Additionally, they have attracted considerable attentions in biodegradation and bioremediation owing to environmental pressures. Motivated by industrial demands, crystallographic investigations and catalytic mechanisms of amidases based on structural biology have witnessed a dramatic promotion in the last two decades. The protein structures showed that different types of amidases have their typical stuctural elements, such as the conserved AS domains in signature amidases and the typical architecture of metal-associated active sites in acetamidase/formamidase family amidases. This review provides an overview of recent research advances in various amidases, with a focus on their structural basis of phylogenetics, substrate specificities and catalytic mechanisms as well as their biotechnological applications. As more crystal structures of amidases are determined, the structure/function relationships of these enzymes will also be further elucidated, which will facilitate molecular engineering and design of amidases to meet industrial requirements.
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Affiliation(s)
- Zheming Wu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
| | - Changfeng Liu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
| | - Zhaoyu Zhang
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
| | - Renchao Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
| | - Yuguo Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
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Spinnato D, Schweitzer-Chaput B, Goti G, Ošeka M, Melchiorre P. A Photochemical Organocatalytic Strategy for the α-Alkylation of Ketones by using Radicals. Angew Chem Int Ed Engl 2020; 59:9485-9490. [PMID: 32053279 PMCID: PMC7317845 DOI: 10.1002/anie.201915814] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Indexed: 12/16/2022]
Abstract
Reported herein is a visible‐light‐mediated radical approach to the α‐alkylation of ketones. This method exploits the ability of a nucleophilic organocatalyst to generate radicals upon SN2‐based activation of alkyl halides and blue light irradiation. The resulting open‐shell intermediates are then intercepted by weakly nucleophilic silyl enol ethers, which would be unable to directly attack the alkyl halides through a traditional two‐electron path. The mild reaction conditions allowed functionalization of the α position of ketones with functional groups that are not compatible with classical anionic strategies. In addition, the redox‐neutral nature of this process makes it compatible with a cinchona‐based primary amine catalyst, which was used to develop a rare example of enantioselective organocatalytic radical α‐alkylation of ketones.
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Affiliation(s)
- Davide Spinnato
- ICIQ-Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology, Avenida Països Catalans 16, 43007, Tarragona, Spain
| | - Bertrand Schweitzer-Chaput
- ICIQ-Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology, Avenida Països Catalans 16, 43007, Tarragona, Spain
| | - Giulio Goti
- ICIQ-Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology, Avenida Països Catalans 16, 43007, Tarragona, Spain
| | - Maksim Ošeka
- ICIQ-Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology, Avenida Països Catalans 16, 43007, Tarragona, Spain
| | - Paolo Melchiorre
- ICIQ-Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology, Avenida Països Catalans 16, 43007, Tarragona, Spain.,ICREA, Passeig Lluís Companys 23, 08010, Barcelona, Spain
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22
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Spinnato D, Schweitzer‐Chaput B, Goti G, Ošeka M, Melchiorre P. A Photochemical Organocatalytic Strategy for the α‐Alkylation of Ketones by using Radicals. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915814] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Davide Spinnato
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
| | - Bertrand Schweitzer‐Chaput
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
| | - Giulio Goti
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
| | - Maksim Ošeka
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
| | - Paolo Melchiorre
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
- ICREA Passeig Lluís Companys 23 08010 Barcelona Spain
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23
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Trost BM, Hung C(J, Mata G. Zweikernige Metall‐ProPhenol‐Katalysatoren: Entwicklung und Anwendungen in der Synthese. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201909692] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Barry M. Trost
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305 USA
| | - Chao‐I (Joey) Hung
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305 USA
| | - Guillaume Mata
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305 USA
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24
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Uddin MN, Knight JD, Rastelli EJ, Soubra-Ghaoui C, Albright TA, Wu CH, Wu JI, Coltart DM. On the Mechanism of the Asymmetric Aldol Addition of Chiral N-Amino Cyclic Carbamate Hydrazones: Evidence of Non-Curtin-Hammett Behavior. Chemistry 2019; 25:16037-16047. [PMID: 31650641 PMCID: PMC7182504 DOI: 10.1002/chem.201902388] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 10/19/2019] [Indexed: 01/25/2023]
Abstract
he mechanistic details of the aldol addition of N-amino cyclic carbamate (ACC) hydrazones is provided herein from both an experimental and computational perspective. When the transformation is carried out at room temperature the anti-aldol product is formed exclusively. Under these conditions the anti- and syn-aldolate intermediates are in equilibrium and the transformation is under thermodynamic control. The anti-aldolate that leads to the anti-aldol product was calculated to be 3.7 kcal mol-1 lower in energy at room temperature than that leading to the syn-aldol product, which sufficiently accounts for the exclusive formation of the anti-aldol product. When the reaction is conducted at -78 °C it is under kinetic control and favors formation of the syn-aldol addition product. In this case, it was found that a solvent separated aza-enolate anion and aldehyde form a σ-intermediate in which the lithium cation is coordinated to the aldehyde. The σ-intermediate collapses with a very small activation barrier to form the β-alkoxy hydrazone intermediate. The chiral nonracemic lithium aza-enolate discriminates between the two diastereotopic faces of the pro-chiral aldehyde, and there is no rapid direct pathway that interconverts the two diastereomeric intermediates. Consequently, the reaction does not follow the Curtin-Hammett principle and the stereochemical outcome at low temperature instead depends on the relative energies of the two σ-intermediates.
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Affiliation(s)
- Md. Nasir Uddin
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
| | - John D. Knight
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
| | - Ettore J. Rastelli
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
| | - Chirine Soubra-Ghaoui
- Department of Chemistry and Physics, University of St. Thomas, Houston, Texas 77006 (USA)
| | - Thomas A. Albright
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
| | - Chia-Hua Wu
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
| | - Judy I. Wu
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
| | - Don M. Coltart
- Department of Chemistry, University of Houston, Houston, Texas 77204 (USA)
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25
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Trost BM, Hung C(J, Mata G. Dinuclear Metal‐ProPhenol Catalysts: Development and Synthetic Applications. Angew Chem Int Ed Engl 2019; 59:4240-4261. [DOI: 10.1002/anie.201909692] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Indexed: 12/16/2022]
Affiliation(s)
- Barry M. Trost
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305 USA
| | - Chao‐I (Joey) Hung
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305 USA
| | - Guillaume Mata
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305 USA
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26
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Diaz-Muñoz G, Miranda IL, Sartori SK, de Rezende DC, Alves Nogueira Diaz M. Use of chiral auxiliaries in the asymmetric synthesis of biologically active compounds: A review. Chirality 2019; 31:776-812. [PMID: 31418934 DOI: 10.1002/chir.23103] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 05/13/2019] [Accepted: 05/22/2019] [Indexed: 01/16/2023]
Abstract
This review article describes the use of some of the most popular chiral auxiliaries in the asymmetric synthesis of biologically active compounds. Chiral auxiliaries derived from naturally occurring compounds, such as amino acids, carbohydrates, and terpenes, are considered essential tools for the construction of highly complex molecules. We highlight the auxiliaries of Evans, Corey, Yamada, Enders, Oppolzer, and Kunz, which led to remarkable progress in asymmetric synthesis in the last decades and continue to bring advances until the present day.
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Affiliation(s)
- Gaspar Diaz-Muñoz
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Izabel Luzia Miranda
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Suélen Karine Sartori
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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Brahmachari G, Karmakar I. sp
2-C-H Acetoxylation of Diversely Substituted (E
)-1-(Arylmethylene)-2-phenylhydrazines Using PhI(OAc)2
as Acetoxy Source at Ambient Conditions. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900994] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Goutam Brahmachari
- Laboratory of Natural Products & Organic Synthesis; Department of Chemistry; Visva-Bharati(a Central University); 731 235 Santiniketan- West Bengal India
| | - Indrajit Karmakar
- Laboratory of Natural Products & Organic Synthesis; Department of Chemistry; Visva-Bharati(a Central University); 731 235 Santiniketan- West Bengal India
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Hashimoto Y, Ikeda T, Ida A, Morita N, Tamura O. Inverse-Electron-Demand oxa-Diels-Alder Reactions of α-Keto-β,γ-unsaturated Esters and α,β-Unsaturated Hydrazones. Org Lett 2019; 21:4245-4249. [PMID: 31140822 DOI: 10.1021/acs.orglett.9b01422] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A concise synthetic method for dihydropyrans has been developed by inverse-electron-demand oxa-Diels-Alder reaction of α-keto-β,γ-unsaturated esters with α,β-unsaturated hydrazones as electron-rich olefins. This reaction is catalyzed by Eu(hfc)3 and proceeds in an endo-selective manner. This umpolung cycloaddition affords a variety of substituted dihydropyrans stereoselectively in high yields. In addition, indirect synthesis of formyl-substituted dihydropyran was achieved by dehydrazonation of the cycloadduct. This method is expected to be useful for the synthesis of dihydropyrans and tetrahydropyrans with unusual substitution patterns.
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Affiliation(s)
| | - Takanori Ikeda
- Showa Pharmaceutical University , Machida , Tokyo 194-8543 , Japan
| | - Ayako Ida
- Showa Pharmaceutical University , Machida , Tokyo 194-8543 , Japan
| | - Nobuyoshi Morita
- Showa Pharmaceutical University , Machida , Tokyo 194-8543 , Japan
| | - Osamu Tamura
- Showa Pharmaceutical University , Machida , Tokyo 194-8543 , Japan
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29
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Biosca M, Pàmies O, Diéguez M. Giving a Second Chance to Ir/Sulfoximine-Based Catalysts for the Asymmetric Hydrogenation of Olefins Containing Poorly Coordinative Groups. J Org Chem 2019; 84:8259-8266. [PMID: 31117569 DOI: 10.1021/acs.joc.9b00829] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This work identifies a family of Ir/phosphite-sulfoximine catalysts that has been successfully used in the asymmetric hydrogenation of olefins with poorly coordinative or noncoordinative groups. In comparison with analogue Ir/phosphine-sulfoximine catalysts previously reported, the presence of a phosphite group extended the range of olefins than can be efficiently hydrogenated. High enantioselectivities, comparable to the best ones reported, have been achieved for a wide range of olefins containing relevant poorly coordinative groups such as α,β-unsaturated enones, esters, lactones, and lactams as well as alkenylboronic esters.
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Affiliation(s)
- Maria Biosca
- Universitat Rovira i Virgili , Departament de Química Física i Inorgànica , C/Marcel·lí Domingo 1 , 43007 Tarragona , Spain
| | - Oscar Pàmies
- Universitat Rovira i Virgili , Departament de Química Física i Inorgànica , C/Marcel·lí Domingo 1 , 43007 Tarragona , Spain
| | - Montserrat Diéguez
- Universitat Rovira i Virgili , Departament de Química Física i Inorgànica , C/Marcel·lí Domingo 1 , 43007 Tarragona , Spain
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30
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Hashimoto Y, Abe R, Morita N, Tamura O. Inverse-electron-demand Diels-Alder reactions of α,β-unsaturated hydrazones with 3-methoxycarbonyl α-pyrones. Org Biomol Chem 2018; 16:8913-8916. [PMID: 30422144 DOI: 10.1039/c8ob02132e] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inverse-electron-demand Diels-Alder reactions of 3-electron-withdrawing group substituted α-pyrones with α,β-unsaturated hydrazones as electron-rich counterparts are catalyzed by Eu(hfc)3 to afford bicyclic lactone cycloadducts. This is an example of umpolung cycloaddition based on functional transformation of carbonyls to hydrazones. A subsequent dehydrazonation reaction enables indirect synthesis of carbonyl group-containing bicyclic lactones, which cannot be easily obtained by the cycloaddition of α-pyrones and enals.
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31
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Huynh U, McDonald SL, Lim D, Uddin MN, Wengryniuk SE, Dey S, Coltart DM. Formation, Alkylation, and Hydrolysis of Chiral Nonracemic N-Amino Cyclic Carbamate Hydrazones: An Approach to the Enantioselective α-Alkylation of Ketones. J Org Chem 2018; 83:12951-12964. [PMID: 30200759 DOI: 10.1021/acs.joc.8b00655] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The α-alkylation of ketones is a fundamental synthetic transformation. The development of asymmetric variants of this reaction is important given that numerous natural products, drugs, and related compounds exist as α-functionalized ketones or derivatives thereof. We previously reported our preliminary studies on the development of a new enantioselective ketone α-alkylation procedure using N-amino cyclic carbamate (ACC) auxiliaries. In comparison to other auxiliary-based methods, ACC alkylation offers a number of advantages and is both highly enantioselective and high yielding. Herein, we provide a full account of our studies on the enantioselective ACC ketone α-alkylation method.
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Affiliation(s)
- Uyen Huynh
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
| | - Stacey L McDonald
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
| | - Daniel Lim
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
| | - Md Nasir Uddin
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
| | - Sarah E Wengryniuk
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
| | - Sumit Dey
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
| | - Don M Coltart
- Department of Chemistry , University of Houston , Houston , Texas 77204 , United States
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Abstract
The alkylation of enolates is one of the backbones of ketone chemistry, yet in practice it suffers from numerous limitations due to problems of regiochemistry (including O- versus C-alkylation), multiple alkylations, self-condensation, competing elimination, and incompatibility with many polar groups that have to be protected. Over the years, various solutions have been devised to overcome these difficulties, such as the employment of auxiliary ester or sulfone groups to modify the p Ka of the enolizable hydrogens, the passage by the corresponding hydrazones, the use of transition-metal-catalyzed redox systems to formally alkylate ketones with alcohols, etc. Most of these hurdles disappear upon switching to α-ketonyl radicals. Radicals are tolerant of most polar functions, and radical additions to flat sp2 centers are generally easier to accomplish than enolate substitution at tetrahedral sp3 carbons. The main stumbling block, however, has been a lack of generally applicable methods for the generation and intermolecular capture of α-ketonyl radicals. We have found over the past years that the degenerative exchange of xanthates represents in many ways an ideal solution to this problem. It overcomes essentially all of the difficulties faced by other radical processes because of its unique ability to reversibly store reactive radicals in a dormant, nonreactive form. The lifetime of the radicals can therefore be significantly enhanced, even in the concentrated medium needed for bimolecular additions, while at the same time regulating their absolute and relative concentrations. The ability to perform intermolecular additions to highly functionalized alkene partners opens up numerous possibilities for rapid and convergent access to complex structures. Of particular importance is the elaboration of ketones that are prone to self-condensation, such trifluoroacetone, and of base-sensitive ketones, such as chloro- and dichloroacetone, since the products can be used for the synthesis of a myriad fluorinated and heteroaromatic compounds of relevance to medicinal chemistry and agrochemistry. The formal distal dialkylation of ketones, also of utmost synthetic interest, is readily accomplished, allowing convenient access to a wide array of useful ketone building blocks. Cascade processes can be implemented and, in alliance with powerful classical reactions (aldol, alkylative Birch reductions, etc.), furnish a quick route to complex polycyclic scaffolds. Furthermore, the presence of the xanthate group in the adducts can be exploited to obtain a variety of arenes and heteroarenes, such as pyrroles, thiophenes, naphthalenes, and pyridines, as well as enones, dienes, and cyclopropanes. Last but not least, the reagents and most of the starting materials are exceedingly cheap, and the reactions are safe and easy to scale up.
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Affiliation(s)
- Samir Z. Zard
- Laboratoire de Synthèse Organique, CNRS UMR 7652 Ecole Polytechnique, 91128 Palaiseau Cedex, France
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33
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Uddin MN, Tarsis EM, Wu CH, Wu JI, Coltart DM. A Mismatch-Free Strategy for the Diastereoselective α,α-Bisalkylation of Chiral Nonracemic Methyl Ketones. Org Lett 2018; 20:3723-3727. [PMID: 29897766 DOI: 10.1021/acs.orglett.8b01146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A chiral auxiliary-based diastereoselective transformation that entirely avoids the stereochemically mismatched pairing, providing equally high levels of asymmetric induction in the formation of each diastereomer is described. In particular, we show that chiral nonracemic methyl ketones undergo α,α-bisalkylation using phenylalanine-derived N-amino cyclic carbamate (ACC) auxiliaries with essentially perfect diastereoselectivity, as well as excellent yield and regioselectivity. Significantly, with the use of a single enantiomer of the auxiliary, either diastereomeric product can be synthesized with an equally high level of asymmetric induction.
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Affiliation(s)
- Md Nasir Uddin
- Department of Chemistry , University of Houston , Houston , Texas 77204-5003 , United States
| | - Emily M Tarsis
- Department of Chemistry , University of Houston , Houston , Texas 77204-5003 , United States
| | - Chia-Hua Wu
- Department of Chemistry , University of Houston , Houston , Texas 77204-5003 , United States
| | - Judy I Wu
- Department of Chemistry , University of Houston , Houston , Texas 77204-5003 , United States
| | - Don M Coltart
- Department of Chemistry , University of Houston , Houston , Texas 77204-5003 , United States
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34
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Harned AM. From determination of enantiopurity to the construction of complex molecules: The Horeau principle and its application in synthesis. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.05.056] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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35
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Lee JTD, Zhao Y. Direct Enantioselective α-Allylation of Unfunctionalized Cyclic Ketones with Alkynes through Pd-Amine Cooperative Catalysis. Chemistry 2018; 24:9520-9524. [DOI: 10.1002/chem.201802273] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Indexed: 01/08/2023]
Affiliation(s)
- Jin Tu Danence Lee
- Department of Chemistry; National University of Singapore; 3 Science Drive 3 Singapore 117543 Singapore
| | - Yu Zhao
- Department of Chemistry; National University of Singapore; 3 Science Drive 3 Singapore 117543 Singapore
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36
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Prieto A, Bouyssi D, Monteiro N. Radical-Mediated Formal C(sp2
)-H Functionalization of Aldehyde-Derived N
,N
-Dialkylhydrazones. European J Org Chem 2018. [DOI: 10.1002/ejoc.201701600] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Alexis Prieto
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Univ Lyon; Université Claude Bernard Lyon 1; 69622 Villeurbanne France
| | - Didier Bouyssi
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Univ Lyon; Université Claude Bernard Lyon 1; 69622 Villeurbanne France
| | - Nuno Monteiro
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Univ Lyon; Université Claude Bernard Lyon 1; 69622 Villeurbanne France
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37
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Xu P, Li W, Xie J, Zhu C. Exploration of C-H Transformations of Aldehyde Hydrazones: Radical Strategies and Beyond. Acc Chem Res 2018; 51:484-495. [PMID: 29359909 DOI: 10.1021/acs.accounts.7b00565] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The chemistry of hydrazones has gained great momentum due to their involvement throughout the evolution of organic synthesis. Herein, we discuss the tremendous developments in both the methodology and application of hydrazones. Hydrazones can be recognized not only as synthetic equivalents to aldehydes and ketones but also as versatile synthetic building blocks. Consequently, they can participate in a range of practical synthetic transformations. Furthermore, hydrazone derivatives display a broad array of biological activities and have been widely applied as pharmaceuticals. Owing to the weak directing group effect of simple aldehydes and ketones in C-H bond functionalizations, the C-H bond functionalizations of hydrazones that have been developed in the past five years represent a significant step forward. These novel transformations open a new door to a broader library of functionalized and complex small molecules. Moreover, a wide range of biologically important N-heterocycles (dihydropyrazoles, pyrazoles, indazoles, cinnolines, etc.) can be efficiently synthesized in an atom- and step-economical manner through single, double, or triple C-H bond functionalizations of hydrazones. Both radical C-H functionalizations and transition-metal-catalyzed directing-group strategies have enhanced the synthetic utility of hydrazones in the chemical community because these strategies solve the long-standing challenge of C-H functionalizations adjacent to aldehydes and ketones. We began this study based on our ongoing interest in visible-light photoredox catalysis. Visible-light photoredox catalysis has become a powerful tool in contemporary synthetic chemistry due to its remarkable advantages in sustainability and use of radical chemistry. By exploiting a photoredox-catalyzed aminyl radical polar crossover (ARPC) strategy, we successfully achieved visible-light-induced C(sp2)-H difluoroalkylation, trifluoromethylation, and perfluoroalkylation of aldehyde-derived hydrazones. This intriguing result was later applied in the C(sp2)-H amination of hydrazones and a cascade cyclization reaction for the synthesis of polycyclic compounds. Encouraged by this redox-neutral C-H functionalization of aldehyde hydrazones, we extended the oxidative C-H/P-H cross-coupling method, which represents a novel and efficient method for the synthesis of α-iminophosphine oxides. Furthermore, an elegant [3 + 2] cycloaddition of azides and aldehyde hydrazones for the synthesis of functionalized tetrazoles was advantageously developed during our investigation of the oxidative C(sp2)-H azidation of aldehyde hydrazones with TMSN3. The sequential C(sp2)-H/C(sp3)-H bond functionalization of aldehyde-derived hydrazones with simple 2,2-dibromo-1,3-dicarbonyls was achieved by employing relay photoredox catalysis, and it provides a novel method of accessing bioactive fused dihydropyrazole derivatives. The notable feature of this approach was further reflected in the formal [4 + 1] annulation of aldehyde-derived N-tetrahydroisoquinoline hydrazones with 2-bromo-1,3-dicarbonyls. To complement these radical C-H functionalization strategies, we recently applied a directing-group strategy in the Rh-catalyzed C(aldehyde)-H functionalization of aldehyde-derived hydrazones for the synthesis of distinctive and bioactive 1H-indazole scaffolds. In summary, this Account presents recent contributions to the exploration, development, mechanistic insights, and synthetic applications of C-H bond functionalizations of aldehyde hydrazones.
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Affiliation(s)
- Pan Xu
- State
Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of
Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Weipeng Li
- State
Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of
Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Jin Xie
- State
Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of
Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Chengjian Zhu
- State
Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of
Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Shanghai 200032, P. R. China
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Gerleve C, Kischkewitz M, Studer A. Synthese α-chiraler Ketone und chiraler Alkane durch eine radikalisch/ionische Kreuzungsreaktion von Vinyl-Bor-At-Komplexen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201711390] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Carolin Gerleve
- Westfälische Wilhelms-Universität; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| | - Marvin Kischkewitz
- Westfälische Wilhelms-Universität; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| | - Armido Studer
- Westfälische Wilhelms-Universität; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
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39
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Gerleve C, Kischkewitz M, Studer A. Synthesis of α-Chiral Ketones and Chiral Alkanes Using Radical Polar Crossover Reactions of Vinyl Boron Ate Complexes. Angew Chem Int Ed Engl 2018; 57:2441-2444. [PMID: 29239507 PMCID: PMC5838550 DOI: 10.1002/anie.201711390] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Indexed: 12/15/2022]
Abstract
Vinyl boron ate complexes of enantioenriched secondary alkyl pinacolboronic esters undergo stereospecific radical‐induced 1,2‐migration in radical polar crossover reactions. In this three‐component process various commercially available alkyl iodides act as radical precursors and light is used for chain initiation. Subsequent oxidation and protodeborylation leads to valuable α‐chiral ketones and chiral alkanes, respectively, with excellent enantiopurity.
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Affiliation(s)
- Carolin Gerleve
- Westfälische Wilhelms-Universität, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
| | - Marvin Kischkewitz
- Westfälische Wilhelms-Universität, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
| | - Armido Studer
- Westfälische Wilhelms-Universität, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
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40
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Heterocyclic Chiral Auxiliaries in Total Synthesis of Natural Products. TOPICS IN HETEROCYCLIC CHEMISTRY 2018. [DOI: 10.1007/7081_2018_26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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41
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Zhang H, Yao Q, Cao W, Ge S, Xu J, Liu X, Feng X. Catalytic enantioselective ene-type reactions of vinylogous hydrazone: construction of α-methylene-γ-butyrolactone derivatives. Chem Commun (Camb) 2018; 54:12511-12514. [DOI: 10.1039/c8cc07567k] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Catalytic asymmetric ene-type reactions of vinylogous hydrazone with isatins, α-ketoester, imines and aldehydes were accomplished which gave an environmentally friendly, straightforward approach to afford bioactive chiral α-methylene-γ-butyrolactone derivatives.
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Affiliation(s)
- Hang Zhang
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
| | - Qian Yao
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
| | - Weidi Cao
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
| | - Shulin Ge
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
| | - Jinxiu Xu
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology
- Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
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42
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Gómez-Palomino A, Barrio A, García-Lorente P, Romea P, Urpí F, Font-Bardia M. Substrate-Controlled Michael Additions of Titanium Enolates from Chiral α-Benzyloxy Ketones to Conjugated Nitroalkenes. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Alejandro Gómez-Palomino
- Departament de Química Inorgànica i Orgànica; Secció de Química Orgànic; and Institut de Biomedicina (IBUB); Universitat de Barcelona; Carrer Martí i Franqués 1-11 08028 Barcelona Catalonia Spain
| | - Adrián Barrio
- Departament de Química Inorgànica i Orgànica; Secció de Química Orgànic; and Institut de Biomedicina (IBUB); Universitat de Barcelona; Carrer Martí i Franqués 1-11 08028 Barcelona Catalonia Spain
| | - Pedro García-Lorente
- Departament de Química Inorgànica i Orgànica; Secció de Química Orgànic; and Institut de Biomedicina (IBUB); Universitat de Barcelona; Carrer Martí i Franqués 1-11 08028 Barcelona Catalonia Spain
| | - Pedro Romea
- Departament de Química Inorgànica i Orgànica; Secció de Química Orgànic; and Institut de Biomedicina (IBUB); Universitat de Barcelona; Carrer Martí i Franqués 1-11 08028 Barcelona Catalonia Spain
| | - Fèlix Urpí
- Departament de Química Inorgànica i Orgànica; Secció de Química Orgànic; and Institut de Biomedicina (IBUB); Universitat de Barcelona; Carrer Martí i Franqués 1-11 08028 Barcelona Catalonia Spain
| | - Mercè Font-Bardia
- Unitat de Difracció de R-X. CCiTUB; Universitat de Barcelona; Carrer Solé i Sabarís 1-3 08028 Barcelona Catalonia Spain
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43
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Li Y, Jackson KE, Charlton A, Le Neve-Foster B, Khurshid A, Rudy HKA, Thompson AL, Paton RS, Hodgson DM. Asymmetric Induction in C-Alkylation of Tropane-Derived Enamines: Congruence Between Computation and Experiment. J Org Chem 2017; 82:10479-10488. [DOI: 10.1021/acs.joc.7b01954] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yifei Li
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Kelvin E. Jackson
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Andrew Charlton
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Ben Le Neve-Foster
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Asma Khurshid
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Heinrich-K. A. Rudy
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Amber L. Thompson
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - Robert S. Paton
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
| | - David. M. Hodgson
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield
Road, Oxford OX1 3TA, U.K
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44
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Vatsadze SZ, Medved’ko AV, Kurzeev SA, Pokrovskiy OI, Parenago OO, Kostenko MO, Ananyev IV, Lyssenko KA, Lemenovsky DA, Kazankov GM, Lunin VV. Stereocontrol in Preparation of Cyclopalladated Alkylaromatic Oximes and Evaluation of Their Stereoselective Esterase-Type Catalytic Activity. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00410] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sergey Z. Vatsadze
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Aleksei V. Medved’ko
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Sergey A. Kurzeev
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | | | - Olga O. Parenago
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Mikhail O. Kostenko
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | | | | | - Dmitri A. Lemenovsky
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Gregory M. Kazankov
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Valery V. Lunin
- Department
of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
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45
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Cano R, Zakarian A, McGlacken GP. Direct Asymmetric Alkylation of Ketones: Still Unconquered. Angew Chem Int Ed Engl 2017; 56:9278-9290. [PMID: 28497890 DOI: 10.1002/anie.201703079] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/27/2017] [Indexed: 01/07/2023]
Abstract
The alkylation of ketones is taught at basic undergraduate level. In many cases this transformation leads to the formation of a new stereogenic center. However, the apparent simplicity of the transformation is belied by a number of problems. So much so, that a general method for the direct asymmetric alkylation of ketones remains an unmet target. Despite the advancement of organocatalysis and transition-metal catalysis, neither field has provided an adequate solution. Indeed, even use of an efficient and general stoichiometric chiral reagent has yet to be reported. Herein we describe the state-of-the-art in terms of direct alkylation reactions of some carbonyl groups. We outline the limited progress that has been made with ketones, and potential routes towards ultimately achieving a widely applicable methodology for the asymmetric alkylation of ketones.
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Affiliation(s)
- Rafael Cano
- Department of Chemistry, University College Cork, Cork, Ireland.,Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Gerard P McGlacken
- Department of Chemistry, University College Cork, Cork, Ireland.,Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
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46
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Cano R, Zakarian A, McGlacken GP. Direkte asymmetrische Alkylierung von Ketonen: noch immer ein unerreichtes Ziel. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201703079] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Rafael Cano
- Department of Chemistry; University College Cork; Cork Irland
- Analytical and Biological Chemistry Research Facility; University College Cork; Cork Irland
| | - Armen Zakarian
- Department of Chemistry and Biochemistry; University of California; Santa Barbara CA 93106 USA
| | - Gerard P. McGlacken
- Department of Chemistry; University College Cork; Cork Irland
- Analytical and Biological Chemistry Research Facility; University College Cork; Cork Irland
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47
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Li J, Dawood RS, Qin S, Liu T, Liu S, Stockman RA, Jiang S, Yang G. Palladium-catalysed α-allylation of chiral sulfinimines derived from symmetric cyclic ketones. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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48
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Hashimoto Y, Ishiwata H, Tachikawa S, Ban S, Morita N, Tamura O. Utilization of electron-donating α,β-unsaturated oximes: regioselective inverse 1,3-dipolar cycloaddition of nitrones. Chem Commun (Camb) 2017; 53:2685-2688. [PMID: 28197607 DOI: 10.1039/c7cc00505a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The cycloaddition of nitrones with α,β-unsaturated carbonyl compounds (enones) afforded predominantly 4-acylisoxazolidines, whereas the cycloaddition of the corresponding oximes afforded 5-iminoisoxazolidines. This inverse regioselection is due to HOMO activation by the oxime functionality.
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Affiliation(s)
| | | | - Soko Tachikawa
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan.
| | - Shintaro Ban
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan.
| | - Nobuyoshi Morita
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan.
| | - Osamu Tamura
- Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan.
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49
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Vega JA, Alonso JM, Méndez G, Ciordia M, Delgado F, Trabanco AA. Continuous Flow α-Arylation of N,N-Dialkylhydrazones under Visible-Light Photoredox Catalysis. Org Lett 2017; 19:938-941. [PMID: 28181814 DOI: 10.1021/acs.orglett.7b00117] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The first direct α-arylation of aldehyde-derived N,N-dialkylhydrazones with electron deficient aryl and heteroaryl cyanides under visible-light photoredox catalysis has been developed. Structurally complex α,α'-diaryl-N,N-cycloalkylhydrazones were obtained in moderate yields by repetition of the direct arylation protocol. A continuous-flow procedure for the preparation of α-aryl-N,N-dialkylhydrazones on a multigram scale has also been established.
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Affiliation(s)
- Juan A Vega
- Neuroscience Medicinal Chemistry, Janssen Research & Development , Jarama 75A, 45007 Toledo, Spain
| | - José Manuel Alonso
- Neuroscience Medicinal Chemistry, Janssen Research & Development , Jarama 75A, 45007 Toledo, Spain
| | - Gabriela Méndez
- Neuroscience Medicinal Chemistry, Janssen Research & Development , Jarama 75A, 45007 Toledo, Spain
| | - Myriam Ciordia
- Neuroscience Medicinal Chemistry, Janssen Research & Development , Jarama 75A, 45007 Toledo, Spain
| | - Francisca Delgado
- Neuroscience Medicinal Chemistry, Janssen Research & Development , Jarama 75A, 45007 Toledo, Spain
| | - Andrés A Trabanco
- Neuroscience Medicinal Chemistry, Janssen Research & Development , Jarama 75A, 45007 Toledo, Spain
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50
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