1
|
Momiyama N, Honda Y, Suzuki T, Jongwohan C. Computational Studies on Reaction Mechanisms and Origin of Stereoselectivity in the [1,3]‐Rearrangement of Ene‐Aldimines. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Norie Momiyama
- Institute for Molecular Science Okazaki, Aichi 444-8787 Japan
- SOKENDAI The Graduate University for Advanced Studies) Okazaki, Aichi 444-8787 Japan
| | - Yasushi Honda
- West Japan Office, HPC Systems Inc. 646 Nijohanjikicho, Shimogyo-ku Kyoto 600-8412 Japan
| | | | - Chanantida Jongwohan
- Institute for Molecular Science Okazaki, Aichi 444-8787 Japan
- SOKENDAI The Graduate University for Advanced Studies) Okazaki, Aichi 444-8787 Japan
| |
Collapse
|
2
|
Tiwari VK, Powell DR, Broussy S, Berkowitz DB. Rapid Enantioselective and Diastereoconvergent Hybrid Organic/Biocatalytic Entry into the Oseltamivir Core. J Org Chem 2021; 86:6494-6503. [PMID: 33857378 DOI: 10.1021/acs.joc.1c00326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A formal synthesis of the antiviral drug (-)-oseltamivir (Tamiflu) has been accomplished starting from m-anisic acid via a dissolving metal or electrochemical Birch reduction. The correct absolute stereochemistry is efficiently set through enzyme-catalyzed carbonyl reduction on the resultant racemic α,β-unsaturated ketone. A screen of a broad ketoreductase (KRED) library identified several that deliver the desired allylic alcohol with nearly perfect facial selectivity at the new center for each antipodal substrate, indicating that the enzyme also is able to completely override inherent diastereomeric bias in the substrate. Conversion is complete, with d-glucose serving as the terminal hydride donor (glucose dehydrogenase). For each resulting diastereomeric secondary alcohol, O/N-interconversion is then efficiently effected either by synfacial [3,3]-sigmatropic allylic imidate rearrangement or by direct, stereoinverting N-Mitsunobu chemistry. Both stereochemical outcomes have been confirmed crystallographically. The α,β-unsaturation is then introduced via an α-phenylselenylation/oxidation/pyrolysis sequence to yield the targeted (S)-N-acyl-protected 5-amino-1,3-cyclohexadiene carboxylates, key advanced intermediates for oseltamivir pioneered by Corey (N-Boc) and Trost (N-phthalamido), respectively.
Collapse
Affiliation(s)
- Virendra K Tiwari
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588, United States
| | - Douglas R Powell
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Sylvain Broussy
- University of Paris, CiTCoM, 8038 CNRS, U 1268 INSERM, F-75006 Paris, France
| | - David B Berkowitz
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588, United States
| |
Collapse
|
3
|
Li H, Fan W, Hong X. Understanding the axial chirality control of quinidine-derived ammonium cation-directed O-alkylation: a computational study. Org Biomol Chem 2019; 17:1916-1923. [PMID: 30280168 DOI: 10.1039/c8ob02173b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
As a privileged chiral scaffold, cinchona alkaloid and its derivatives have reached remarkable success in catalytic asymmetric organic synthesis. In addition to the wide applications of point chirality control, Smith and co-workers recently discovered a quinidine-derived ammonium cation-catalyzed O-alkylation of tetralones, providing an effective approach for the synthesis of axially chiral biaryls. Using density functional theory (DFT) calculations, we studied the reaction mechanism and origins of enantioselectivity of this novel transformation. A stepwise strategy is adopted to ensure efficient and thorough exploration of the massive conformational space of transition state. Our computations suggested that enolate oxygen forms two hydrogen bonds with the chiral ammonium catalyst, and the non-covalent interactions between the cationic benzylic fragment and the methoxy group of enolate plays a critical role in determining the enantioselectivity.
Collapse
Affiliation(s)
- Han Li
- Department of Chemistry, Zhejiang University, Hangzhou, 310027, China.
| | | | | |
Collapse
|
4
|
Rajale T, Sharma S, Unruh DK, Stroud DA, Birney DM. A pseudopericyclic [3,5]-sigmatropic rearrangement of a coumarin trichloroacetimidate derivative. Org Biomol Chem 2018; 16:874-879. [DOI: 10.1039/c7ob02335a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A Woodward–Hoffmann forbidden, eight-centered transition state leads to the sole product of a pentadienyl imidate rearrangement.
Collapse
Affiliation(s)
- Trideep Rajale
- Department of Chemistry and Biochemistry
- Texas Tech University
- Lubbock
- USA
- Center for Integrated Nanotechnologies
| | - Shikha Sharma
- Department of Chemistry and Biochemistry
- Texas Tech University
- Lubbock
- USA
| | - Daniel K. Unruh
- Department of Chemistry and Biochemistry
- Texas Tech University
- Lubbock
- USA
| | - Daniel A. Stroud
- Department of Chemistry and Biochemistry
- Texas Tech University
- Lubbock
- USA
| | - David M. Birney
- Department of Chemistry and Biochemistry
- Texas Tech University
- Lubbock
- USA
| |
Collapse
|
5
|
Li M, Xue XS, Cheng JP. Mechanism and Origins of Stereoinduction in Natural Cinchona Alkaloid Catalyzed Asymmetric Electrophilic Trifluoromethylthiolation of β-Keto Esters with N-Trifluoromethylthiophthalimide as Electrophilic SCF3 Source. ACS Catal 2017. [DOI: 10.1021/acscatal.7b03007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Man Li
- State
Key Laboratory of Elemento-Organic Chemistry, College of Chemistry,
Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, People’s Republic of China
| | - Xiao-Song Xue
- State
Key Laboratory of Elemento-Organic Chemistry, College of Chemistry,
Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, People’s Republic of China
| | - Jin-Pei Cheng
- State
Key Laboratory of Elemento-Organic Chemistry, College of Chemistry,
Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, People’s Republic of China
- Center
of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China
| |
Collapse
|
6
|
Tanriver G, Dedeoglu B, Catak S, Aviyente V. Computational Studies on Cinchona Alkaloid-Catalyzed Asymmetric Organic Reactions. Acc Chem Res 2016; 49:1250-62. [PMID: 27254097 DOI: 10.1021/acs.accounts.6b00078] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Remarkable progress in the area of asymmetric organocatalysis has been achieved in the last decades. Cinchona alkaloids and their derivatives have emerged as powerful organocatalysts owing to their reactivities leading to high enantioselectivities. The widespread usage of cinchona alkaloids has been attributed to their nontoxicity, ease of use, stability, cost effectiveness, recyclability, and practical utilization in industry. The presence of tunable functional groups enables cinchona alkaloids to catalyze a broad range of reactions. Excellent experimental studies have extensively contributed to this field, and highly selective reactions were catalyzed by cinchona alkaloids and their derivatives. Computational modeling has helped elucidate the mechanistic aspects of cinchona alkaloid catalyzed reactions as well as the origins of the selectivity they induce. These studies have complemented experimental work for the design of more efficient catalysts. This Account presents recent computational studies on cinchona alkaloid catalyzed organic reactions and the theoretical rationalizations behind their effectiveness and ability to induce selectivity. Valuable efforts to investigate the mechanisms of reactions catalyzed by cinchona alkaloids and the key aspects of the catalytic activity of cinchona alkaloids in reactions ranging from pharmaceutical to industrial applications are summarized. Quantum mechanics, particularly density functional theory (DFT), and molecular mechanics, including ONIOM, were used to rationalize experimental findings by providing mechanistic insights into reaction mechanisms. B3LYP with modest basis sets has been used in most of the studies; nonetheless, the energetics have been corrected with higher basis sets as well as functionals parametrized to include dispersion M05-2X, M06-2X, and M06-L and functionals with dispersion corrections. Since cinchona alkaloids catalyze reactions by forming complexes with substrates via hydrogen bonds and long-range interactions, the use of split valence triple-ζ basis sets including diffuse and polarization functions on heavy atoms and polarization functions on hydrogens are recommended. Most of the studies have used the continuum-based models to mimic the condensed phase in which organocatalysts function; in some cases, explicit solvation was shown to yield better quantitative agreement with experimental findings. The conformational behavior of cinchona alkaloids is also highlighted as it is expected to shed light on the origin of selectivity and pave the way to a comprehensive understanding of the catalytic mechanism. The ultimate goal of this Account is to provide an up-to-date overlook on cinchona alkaloid catalyzed chemistry and provide insight for future studies in both experimental and theoretical fields.
Collapse
Affiliation(s)
- Gamze Tanriver
- Department
of Chemistry, Bogazici University, Bebek, Istanbul 34342, Turkey
| | - Burcu Dedeoglu
- Foundations
Development Directorate, Sabancı University, Tuzla-Orhanlı, Istanbul 34956, Turkey
| | - Saron Catak
- Department
of Chemistry, Bogazici University, Bebek, Istanbul 34342, Turkey
| | - Viktorya Aviyente
- Department
of Chemistry, Bogazici University, Bebek, Istanbul 34342, Turkey
| |
Collapse
|
7
|
Kamachi T, Yoshizawa K. Low-Mode Conformational Search Method with Semiempirical Quantum Mechanical Calculations: Application to Enantioselective Organocatalysis. J Chem Inf Model 2016; 56:347-53. [DOI: 10.1021/acs.jcim.5b00671] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Takashi Kamachi
- Institute
for Materials Chemistry
and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Kazunari Yoshizawa
- Institute
for Materials Chemistry
and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| |
Collapse
|
8
|
Grayson MN, Houk KN. Cinchona Alkaloid-Catalyzed Asymmetric Conjugate Additions: The Bifunctional Brønsted Acid–Hydrogen Bonding Model. J Am Chem Soc 2016; 138:1170-3. [DOI: 10.1021/jacs.5b13275] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Matthew N. Grayson
- Department
of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
- Centre
for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - K. N. Houk
- Department
of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| |
Collapse
|
9
|
Sharma S, Rajale T, Unruh DK, Birney DM. Competitive Pseudopericyclic [3,3]- and [3,5]-Sigmatropic Rearrangements of Trichloroacetimidates. J Org Chem 2015; 80:11734-43. [DOI: 10.1021/acs.joc.5b01355] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shikha Sharma
- Department of Chemistry and
Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - Trideep Rajale
- Department of Chemistry and
Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - Daniel K. Unruh
- Department of Chemistry and
Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - David M. Birney
- Department of Chemistry and
Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| |
Collapse
|
10
|
Wang F, Yang C, Xue XS, Li X, Cheng JP. A Highly Efficient Chirality Switchable Synthesis of Dihydropyran-Fused Benzofurans by Fine-Tuning the Phenolic Proton of β-Isocupreidine (β-ICD) Catalyst with Methyl. Chemistry 2015; 21:10443-9. [PMID: 26059531 DOI: 10.1002/chem.201501145] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Indexed: 01/03/2023]
Abstract
A highly enantioselective β-isocupreidine (β-ICD) catalyzed synthesis of dihydropyran-fused benzofurans through [4+2] cycloaddition of allenoates and benzofuranone alkenes was developed. Switchable chirality inversion of cycloaddition products was achieved by replacing the phenolic proton of the catalyst with a methyl, demonstrating an amazing effect of minimal structural variation on inverting enantioselectivity. DFT calculations were utilized to elucidate the origin of the observed phenomena. Computation also provided a clue for a rational design in which the multi-hydrogen bond with the alcohol additive was found to improve the enantioselectivity of the cycloaddition. Finally, the substrate scope was examined, in which a number of functionalized dihydropyran-fused benzofurans could be obtained in high yields (up to 97 %) with very good regio- (>20:1) and enantioselectivities (up to 98:2 e.r.).
Collapse
Affiliation(s)
- Feng Wang
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Department of Chemistry, Nankai University, Tianjin 300071 (P.R. China)
| | - Chen Yang
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Department of Chemistry, Nankai University, Tianjin 300071 (P.R. China)
| | - Xiao-Song Xue
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Department of Chemistry, Nankai University, Tianjin 300071 (P.R. China)
| | - Xin Li
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Department of Chemistry, Nankai University, Tianjin 300071 (P.R. China).
| | - Jin-Pei Cheng
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Department of Chemistry, Nankai University, Tianjin 300071 (P.R. China).
| |
Collapse
|
11
|
Kalyva M, Zografos AL, Kapourani E, Giambazolias E, Devel L, Papakyriakou A, Dive V, Lazarou YG, Georgiadis D. Probing the Mechanism of Allylic Substitution of Morita–Baylis–Hillman Acetates (MBHAs) by using the Silyl Phosphonite Paradigm: Scope and Applications of a Versatile Transformation. Chemistry 2015; 21:3278-89. [DOI: 10.1002/chem.201405626] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Indexed: 01/31/2023]
Affiliation(s)
- Maria Kalyva
- Department of Chemistry, Laboratory of Organic Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771, Athens (Greece), Fax: (+30) 210‐727‐4761
| | - Alexandros L. Zografos
- Department of Chemistry, Laboratory of Organic Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771, Athens (Greece), Fax: (+30) 210‐727‐4761
- Present address: Department of Chemistry, Laboratory of Organic Chemistry, Aristotle University of Thessaloniki, University Campus, 54124, Thessaloniki (Greece)
| | - Era Kapourani
- Department of Chemistry, Laboratory of Organic Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771, Athens (Greece), Fax: (+30) 210‐727‐4761
| | - Evaggelos Giambazolias
- Department of Chemistry, Laboratory of Organic Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771, Athens (Greece), Fax: (+30) 210‐727‐4761
| | - Laurent Devel
- CEA‐Saclay, Service d'Ingénierie Moléculaire des Protéines, Labex LERMIT, CEA‐DSV‐iBiTecS, 91191 Gif/Yvette (France)
| | - Athanasios Papakyriakou
- National Center for Scientific Research, “Demokritos”, Aghia Paraskevi Attikis, GR 15310 (Greece)
| | - Vincent Dive
- CEA‐Saclay, Service d'Ingénierie Moléculaire des Protéines, Labex LERMIT, CEA‐DSV‐iBiTecS, 91191 Gif/Yvette (France)
| | - Yannis G. Lazarou
- National Center for Scientific Research, “Demokritos”, Aghia Paraskevi Attikis, GR 15310 (Greece)
| | - Dimitris Georgiadis
- Department of Chemistry, Laboratory of Organic Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771, Athens (Greece), Fax: (+30) 210‐727‐4761
| |
Collapse
|
12
|
Prakash GKS, Wang F, Rahm M, Zhang Z, Ni C, Shen J, Olah GA. The trifluoromethyl group as a conformational stabilizer and probe: conformational analysis of cinchona alkaloid scaffolds. J Am Chem Soc 2014; 136:10418-31. [PMID: 24979676 DOI: 10.1021/ja504376u] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The introduction of the CF3 group on the C9 atom in quinidine can significantly increase the conformational interconversion barrier of the cinchona alkaloid scaffold. With this modification the conformational behavior of cinchona alkaloids in various solvents can be conveniently investigated via (19)F NMR spectroscopy. Based on the reliable conformational distribution information obtained, the accuracy of both theoretical (PCM) and empirical (Kamlet-Taft) solvation models has been assessed using linear free energy relationship methods. The empirical solvation model was found to provide accurate prediction of solvent effects, while PCM demonstrated a relatively low reliability in the present study. Utilizing similar empirical solvation models along with Karplus-type equations, the conformational behavior of quinidine and 9-epi-quinidine has also been investigated. A model SN2 reaction has been presented to reveal the important role of solvent-induced conformational behavior of cinchona alkaloids in their reactivity.
Collapse
Affiliation(s)
- G K Surya Prakash
- Loker Hydrocarbon Research Institute, Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
| | | | | | | | | | | | | |
Collapse
|
13
|
Feng YJ, Lo JX, Lin YC, Huang SL, Wang Y, Liu YH. Tandem Cyclization of Enynes Containing a Thioether or Ether Linkage via Ruthenium Allenylidene and Vinylidene Complexes. Organometallics 2013. [DOI: 10.1021/om400742x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Yi-Jhen Feng
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Ji-Xian Lo
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Ying-Chih Lin
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Shou-Ling Huang
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Yu Wang
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Yi-Hung Liu
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| |
Collapse
|
14
|
Martinková M, Pomikalová K, Gonda J, Vilková M. A common approach to the total synthesis of l-arabino-, l-ribo-C18-phytosphingosines, ent-2-epi-jaspine B and 3-epi-jaspine B from d-mannose. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.07.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
15
|
Xue XS, Li X, Yu A, Yang C, Song C, Cheng JP. Mechanism and Selectivity of Bioinspired Cinchona Alkaloid Derivatives Catalyzed Asymmetric Olefin Isomerization: A Computational Study. J Am Chem Soc 2013; 135:7462-73. [DOI: 10.1021/ja309133z] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Xiao-Song Xue
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xin Li
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ao Yu
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chen Yang
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chan Song
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jin-Pei Cheng
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| |
Collapse
|
16
|
Hintermann L, Ackerstaff J, Boeck F. Inner Workings of a Cinchona Alkaloid Catalyzed Oxa-Michael Cyclization: Evidence for a Concerted Hydrogen-Bond-Network Mechanism. Chemistry 2013; 19:2311-21. [DOI: 10.1002/chem.201203505] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Indexed: 11/09/2022]
|
17
|
Johnston RC, Cheong PHY. C–H⋯O non-classical hydrogen bonding in the stereomechanics of organic transformations: theory and recognition. Org Biomol Chem 2013; 11:5057-64. [DOI: 10.1039/c3ob40828k] [Citation(s) in RCA: 172] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
18
|
Martinková M, Gonda J, Uhríková A, Raschmanová JŠ, Kuchár J. An efficient synthesis of the polar part of sulfamisterin and its analogs. Carbohydr Res 2012; 352:23-36. [DOI: 10.1016/j.carres.2012.02.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/16/2012] [Accepted: 02/17/2012] [Indexed: 11/15/2022]
Affiliation(s)
- Miroslava Martinková
- Institute of Chemical Sciences, Department of Organic Chemistry, P.J. Šafárik University, Moyzesova 11, Sk-040 01 Košice, Slovak Republic.
| | | | | | | | | |
Collapse
|
19
|
Cheong PHY, Legault CY, Um JM, Çelebi-Ölçüm N, Houk KN. Quantum mechanical investigations of organocatalysis: mechanisms, reactivities, and selectivities. Chem Rev 2011; 111:5042-137. [PMID: 21707120 PMCID: PMC3154597 DOI: 10.1021/cr100212h] [Citation(s) in RCA: 429] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Paul Ha-Yeon Cheong
- Oregon State University, Department of Chemistry, 153 Gilbert Hall, Corvallis, OR 97331-4003 USA
| | - Claude Y. Legault
- University of Sherbrooke, Department of Chemistry, 2500 boul. de l’Université, local D1-3029, Sherbrooke (Québec) J1K 2R1 CANADA
| | - Joann M. Um
- University of California Los Angeles, Department of Chemistry and Biochemistry, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569 USA
| | - Nihan Çelebi-Ölçüm
- University of California Los Angeles, Department of Chemistry and Biochemistry, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569 USA
| | - K. N. Houk
- University of California Los Angeles, Department of Chemistry and Biochemistry, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569 USA
| |
Collapse
|
20
|
Martinková M, Gonda J, Pomikalová K, Kožíšek J, Kuchár J. A facile synthesis of D-ribo-C(20)-phytosphingosine and its C2 epimer from D-ribose. Carbohydr Res 2011; 346:1728-38. [PMID: 21703597 DOI: 10.1016/j.carres.2011.05.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 05/23/2011] [Accepted: 05/25/2011] [Indexed: 10/18/2022]
Abstract
A facile synthetic route to d-ribo-C(20)-phytosphingosine 31 and its C2 epimer 32 is described. The Overman rearrangement of allylic trichloroacetimidates derived from the known ribose derivative 7 has been used as the key step. The subsequent functional group interconversions in rearranged products 14 and 15 followed by Wittig olefination, Pd/C-mediated reduction and the removal of protecting groups successfully constructed the final molecules.
Collapse
Affiliation(s)
- Miroslava Martinková
- Department of Organic Chemistry, P.J. Šafárik University, Moyzesova, Košice, Slovak Republic.
| | | | | | | | | |
Collapse
|
21
|
Marcelli T. Organocatalysis:
Cinchona
catalysts. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2011. [DOI: 10.1002/wcms.2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Tommaso Marcelli
- Dipartimento di Chimica, Materiali e Ingegneria Chimica ‘Giulio Natta’, Politecnico di Milano, Milan, Italy
| |
Collapse
|
22
|
Marcelli T, Olimpieri F, Volonterio A. Domino synthesis of 1,3,5-trisubstituted hydantoins: a DFT study. Org Biomol Chem 2011; 9:5156-61. [DOI: 10.1039/c1ob05242j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
23
|
Lee SI, Moon SY, Hwang GS, Ryu DH. Facile Approach to Optically Active α-Alkylidene-β-amino Esters by Thermal Overman Rearrangement. Org Lett 2010; 12:3234-7. [DOI: 10.1021/ol1011746] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sung Il Lee
- Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Korea, and Korea Basic Science Institute and Graduate School of Analytical Science and Technology, Chungnam National University, Seoul, 136-713, Korea
| | - Soon Young Moon
- Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Korea, and Korea Basic Science Institute and Graduate School of Analytical Science and Technology, Chungnam National University, Seoul, 136-713, Korea
| | - Geum-Sook Hwang
- Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Korea, and Korea Basic Science Institute and Graduate School of Analytical Science and Technology, Chungnam National University, Seoul, 136-713, Korea
| | - Do Hyun Ryu
- Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Korea, and Korea Basic Science Institute and Graduate School of Analytical Science and Technology, Chungnam National University, Seoul, 136-713, Korea
| |
Collapse
|
24
|
López-Camacho PY, Joseph-Nathan P, Gordillo-Román B, Suárez-Castillo OR, Morales-Ríos MS. Cascade [1,3]-sigmatropic rearrangements of ketene O,O-acetals: kinetic and DFT level mechanistic studies. J Org Chem 2010; 75:1898-910. [PMID: 20180516 DOI: 10.1021/jo902520z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The regioisomeric alpha-cyano ketene-O,O-dialkyl acetals 2a-e and 4a-e, sequential intermediates in the diazomethane induced conversion of indole alpha-cyano-gamma-lactones 1a-e to 2-indolyl cyanomalonates 5a-e, were isolated and characterized. Formation of the steady-state intermediate cycloprop[b]indoles 3a-e was evidenced by means of NMR and confirmed by the X-ray structure of 3c, demonstrating that the formation of 5a-e from 2a-e proceeds through two consecutive and one parallel unimolecular steps, with intermediates 3a-e formed in reversible processes. Evidence that the reversible reactions proceed via [1,3]-rearrangements is presented. The steady-state kinetic approach applied to intermediate 3 allowed a minimal two consecutive step 2 --> 4--> 5 kinetic model, in which the steric bulkiness of the alkyl substituent affects strongly the associated rate constants, k(1) and k(2), inverting the rate-determining step. The solvation effects enhanced the feasibility of these skeletal rearrangements as they stabilized the transition states to a great extent. The experimental determined thermodynamic parameters and DFT calculations suggest that these cascade rearrangements occur through [1,3]-sigmatropic mechanisms, in which asynchronous bond reorganization processes via four membered pseudopericyclic transition states are highly favorable.
Collapse
Affiliation(s)
- Perla Y López-Camacho
- Departamento de Química, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado 14-740, México, DF, 07000 Mexico
| | | | | | | | | |
Collapse
|
25
|
Chung CP, Chen CC, Lin YC, Liu YH, Wang Y. Reactions of Ruthenium Cp Phosphine Complex with 4,4-Disubstituted-1,6-Enynes: Effect of Methyl Substituents in the Olefinic Fraction. J Am Chem Soc 2009; 131:18366-75. [DOI: 10.1021/ja906745j] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chia-Pei Chung
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | | | | | | | | |
Collapse
|