1
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Ouyang J, Maji R, Leutzsch M, Mitschke B, List B. Design of an Organocatalytic Asymmetric (4 + 3) Cycloaddition of 2-Indolylalcohols with Dienolsilanes. J Am Chem Soc 2022; 144:8460-8466. [PMID: 35523203 PMCID: PMC9121375 DOI: 10.1021/jacs.2c02216] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
![]()
Here we present the
design of a highly enantioselective, catalytic
(4 + 3) cycloaddition of gem-dialkyl 2-indolyl alcohols
and dienolsilanes, enabled by strong and confined IDPi Lewis acids.
The method furnishes novel bicyclo[3.2.2]cyclohepta[b]indoles with up to three stereogenic centers, one of which is quaternary.
A broad substrate scope is accompanied by versatile downstream chemical
modifications. Density functional theory-supported mechanistic studies
shed light on the importance of the in situ generated silylium species
in an overall concerted yet asynchronous cycloaddition.
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Affiliation(s)
- Jie Ouyang
- Max-Planck-Institut für Kohlenforschung, D45470 Mülheim an der Ruhr, Germany
| | - Rajat Maji
- Max-Planck-Institut für Kohlenforschung, D45470 Mülheim an der Ruhr, Germany
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung, D45470 Mülheim an der Ruhr, Germany
| | - Benjamin Mitschke
- Max-Planck-Institut für Kohlenforschung, D45470 Mülheim an der Ruhr, Germany
| | - Benjamin List
- Max-Planck-Institut für Kohlenforschung, D45470 Mülheim an der Ruhr, Germany.,Institute for Chemical Reaction Design and Discovery (WPI-ICRedd), Hokkaido University, Sapporo 001-0021, Japan
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2
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Braddock DC, Limpaitoon N, Oliwa K, O'Reilly D, Rzepa HS, White AJP. A stereoselective hydride transfer reaction with contributions from attractive dispersion force control. Chem Commun (Camb) 2022; 58:4981-4984. [PMID: 35322841 DOI: 10.1039/d2cc01136k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The experimentally determined stereochemical outcome of an unprecedented hydride transfer from a lithium alkoxide to an aldehyde is reported, as deconvoluted by the combined use of a single enantiomer alkoxide in conjunction with a deuterium label. The stereoselective outcome is consistent with a computationally predicted transition state model stabilised by contributions from attractive dispersion forces.
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Affiliation(s)
- D Christopher Braddock
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, UK.
| | - Natnicha Limpaitoon
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, UK.
| | - Krzysztof Oliwa
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, UK.
| | - Daniel O'Reilly
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, UK.
| | - Henry S Rzepa
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, UK.
| | - Andrew J P White
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, UK.
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3
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Koleoso OK, Turner M, Plasser F, Kimber MC. A complementary approach to conjugated N-acyliminium formation through photoredox-catalyzed intermolecular radical addition to allenamides and allencarbamates. Beilstein J Org Chem 2020; 16:1983-1990. [PMID: 32831955 PMCID: PMC7431758 DOI: 10.3762/bjoc.16.165] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022] Open
Abstract
An intermolecular radical addition, using photoredox catalysis, to allenamides and allencarbamates is reported. This transformation synthesizes N-acyl-N’-aryl-N,N’-allylaminals, and proceeds by a conjugated N-acyliminium intermediate that previously has principally been generated by electrophilic activation methods. The radical adds to the central carbon of the allene giving a conjugated N-acyliminium that undergoes nucleophilic addition by arylamines and alcohols.
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Affiliation(s)
- Olusesan K Koleoso
- School of Science, Department of Chemistry, Loughborough University, Loughborough, LE11 3TU, UK.,Department of Pharmaceutical Technology, Moshood Abiola Polytechnic, Abeokuta, Nigeria
| | - Matthew Turner
- School of Science, Department of Chemistry, Loughborough University, Loughborough, LE11 3TU, UK
| | - Felix Plasser
- School of Science, Department of Chemistry, Loughborough University, Loughborough, LE11 3TU, UK
| | - Marc C Kimber
- School of Science, Department of Chemistry, Loughborough University, Loughborough, LE11 3TU, UK
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4
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Holtrop F, Visscher KW, Jupp AR, Slootweg JC. Steric attraction: A force to be reckoned with. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2020. [DOI: 10.1016/bs.apoc.2020.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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5
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Huang WH, Huang GB, Zhu WR, Weng J, Lu G. Transition metal-free synthesis of α-aryl ketones via oxyallyl cation capture with arylboronic acids. Org Chem Front 2020. [DOI: 10.1039/d0qo00447b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
α-Arylated ketones were accessed via oxyallyl cation capture with arylboronic acids in good yields with broad substrate tolerance.
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Affiliation(s)
- Wei-Hua Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-sen University
- Guangzhou 510006
- P. R. China
| | - Gong-Bin Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-sen University
- Guangzhou 510006
- P. R. China
| | - Wen-Run Zhu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-sen University
- Guangzhou 510006
- P. R. China
| | - Jiang Weng
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-sen University
- Guangzhou 510006
- P. R. China
| | - Gui Lu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-sen University
- Guangzhou 510006
- P. R. China
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6
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Nguyen TN, Setthakarn K, May JA. Oxyallyl Cation Capture via Electrophilic Deborylation of Organoboronates: Access to α, α'-Substituted Cyclic Ketones. Org Lett 2019; 21:7837-7840. [PMID: 31536365 DOI: 10.1021/acs.orglett.9b02831] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An umpolung strategy to synthesize α,α'-substituted cyclic ketones through the nucleophilic addition of organoboronates to α-hydroxyl silyl enol ethers is described. The reaction proceeds via the trapping of in situ generated oxyallyl cations via the electrophilic deborylation of C(sp2) and C(sp) borates. This efficient and straightforward method provides direct access to α-substituted silyl enol ethers in high yield with complete regioselectivity. Desilylation in a one-pot procedure provides the corresponding α,α'-disubstituted ketones with high diastereoselectivity.
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Affiliation(s)
- Truong N Nguyen
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Fleming Building Room 112 , Houston , Texas 77204-5003 , United States
| | - Krit Setthakarn
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Fleming Building Room 112 , Houston , Texas 77204-5003 , United States
| | - Jeremy A May
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Fleming Building Room 112 , Houston , Texas 77204-5003 , United States
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7
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Zhang W, Chu J, Cyr AM, Yueh H, Brown LE, Wang TT, Pelletier J, Porco JA. Intercepted Retro-Nazarov Reaction: Syntheses of Amidino-Rocaglate Derivatives and Their Biological Evaluation as eIF4A Inhibitors. J Am Chem Soc 2019; 141:12891-12900. [PMID: 31310112 PMCID: PMC6693944 DOI: 10.1021/jacs.9b06446] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Rocaglates are a family of natural products isolated from the genus Aglaia which possess a highly substituted cyclopenta[b]benzofuran skeleton and inhibit cap-dependent protein synthesis. Rocaglates are attractive compounds due to their potential for inhibiting tumor cell maintenance in vivo by specifically targeting eukaryotic initiation factor 4A (eIF4A) and interfering with recruitment of ribosomes to mRNA. In this paper, we describe an intercepted retro-Nazarov reaction utilizing intramolecular tosyl migration to generate a reactive oxyallyl cation on the rocaglate skeleton. Trapping of the oxyallyl cation with a diverse range of nucleophiles has been used to generate over 50 novel amidino-rocaglate (ADR) and amino-rocaglate derivatives. Subsequently, these derivatives were evaluated for their ability to inhibit cap-dependent protein synthesis where they were found to outperform previous lead compounds including the rocaglate hydroxamate CR-1-31-B.
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Affiliation(s)
- Wenhan Zhang
- Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, MA 02215, United States of America
| | - Jennifer Chu
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada, H3G 1Y6
| | - Andrew M. Cyr
- Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, MA 02215, United States of America
| | - Han Yueh
- Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, MA 02215, United States of America
| | - Lauren E. Brown
- Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, MA 02215, United States of America
| | - Tony T. Wang
- Laboratory of Vector-borne Viral Diseases, Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20903, USA
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada, H3G 1Y6
- Department of Oncology, McGill University, Montreal, Quebec, Canada, H3G 1Y6
- Rosalind & Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada, H3G 1Y6
| | - John A. Porco
- Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, MA 02215, United States of America
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8
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Liu Q, Sun L, Li S, Li X, Qu L, Lan Y, Wei D. Insights into N‐Heterocyclic Carbene (NHC)‐Catalyzed Asymmetric Addition of 2H‐Azirine with Aldehyde. Chem Asian J 2019; 14:2000-2007. [DOI: 10.1002/asia.201900076] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/14/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Qiuli Liu
- The College of Chemistry and Molecular EngineeringZhengzhou University No. 100 Kexue Street Zhengzhou Henan 450001 P. R. China
| | - Ling Sun
- Basic Teaching DepartmentHuanghe Jiaotong University No. 333 Yingbin Road Wuzhi Henan 454950 P. R. China
| | - Shi‐Jun Li
- The College of Chemistry and Molecular EngineeringZhengzhou University No. 100 Kexue Street Zhengzhou Henan 450001 P. R. China
| | - Xue Li
- The College of Chemistry and Molecular EngineeringZhengzhou University No. 100 Kexue Street Zhengzhou Henan 450001 P. R. China
| | - Ling‐Bo Qu
- The College of Chemistry and Molecular EngineeringZhengzhou University No. 100 Kexue Street Zhengzhou Henan 450001 P. R. China
| | - Yu Lan
- The College of Chemistry and Molecular EngineeringZhengzhou University No. 100 Kexue Street Zhengzhou Henan 450001 P. R. China
| | - Donghui Wei
- The College of Chemistry and Molecular EngineeringZhengzhou University No. 100 Kexue Street Zhengzhou Henan 450001 P. R. China
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9
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Maji R, Ugale H, Wheeler SE. Understanding the Reactivity and Selectivity of Fluxional Chiral DMAP-Catalyzed Kinetic Resolutions of Axially Chiral Biaryls. Chemistry 2019; 25:4452-4459. [PMID: 30657217 DOI: 10.1002/chem.201806068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/17/2019] [Indexed: 12/17/2022]
Abstract
Fluxional chiral DMAP-catalyzed kinetic resolutions of axially chiral biaryls were examined using density functional theory. Computational analyses lead to a revised understanding of this reaction in which the interplay of numerous non-covalent interactions control the conformation and flexibility of the active catalyst, the preferred mechanism, and the stereoselectivity. Notably, while the DMAP catalyst itself is confirmed to be highly fluxional, electrostatically driven π⋅⋅⋅π+ interactions render the active, acylated form of the catalyst highly rigid, explaining its pronounced stereoselectivity.
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Affiliation(s)
- Rajat Maji
- Department of Chemistry, Texas A&M University, College Station, TX, 77842, USA
| | - Heena Ugale
- Department of Chemistry, Texas A&M University, College Station, TX, 77842, USA
| | - Steven E Wheeler
- Department of Chemistry, Texas A&M University, College Station, TX, 77842, USA.,Center for Computational Quantum Chemistry, Department of Chemistry, University of Georgia, Athens, GA, 30602, USA
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10
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Cordier M, Archambeau A. (3 + 3) Cycloaddition of Oxyallyl Cations with Nitrones: Diastereoselective Access to 1,2-Oxazinanes. Org Lett 2018; 20:2265-2268. [DOI: 10.1021/acs.orglett.8b00617] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Marie Cordier
- Laboratoire de Chimie Moléculaire, UMR 9168, Ecole Polytechnique, CNRS, 91128 Palaiseau Cedex, France
| | - Alexis Archambeau
- Laboratoire de Synthèse Organique, UMR 7652, Ecole Polytechnique, ENSTA ParisTech, CNRS, 91128 Palaiseau Cedex, France
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11
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Burns JM. Computational evidence for a reaction pathway bifurcation in Sasaki-type (4 + 3)-cycloadditions. Org Biomol Chem 2018; 16:1828-1836. [DOI: 10.1039/c8ob00075a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Evidence for a post-transition state bifurcation in a (4 + 3)-cycloaddition is presented.
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Affiliation(s)
- Jed M. Burns
- School of Chemistry and Molecular Biosciences
- The University of Queensland
- Brisbane
- Australia
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12
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Villar L, Uria U, Martínez JI, Prieto L, Reyes E, Carrillo L, Vicario JL. Enantioselective Oxidative (4+3) Cycloadditions between Allenamides and Furans through Bifunctional Hydrogen-Bonding/Ion-Pairing Interactions. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201704804] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Laura Villar
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Uxue Uria
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Jose I. Martínez
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Liher Prieto
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Efraim Reyes
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Luisa Carrillo
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Jose L. Vicario
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
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13
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Villar L, Uria U, Martínez JI, Prieto L, Reyes E, Carrillo L, Vicario JL. Enantioselective Oxidative (4+3) Cycloadditions between Allenamides and Furans through Bifunctional Hydrogen-Bonding/Ion-Pairing Interactions. Angew Chem Int Ed Engl 2017; 56:10535-10538. [DOI: 10.1002/anie.201704804] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/24/2017] [Indexed: 12/27/2022]
Affiliation(s)
- Laura Villar
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Uxue Uria
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Jose I. Martínez
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Liher Prieto
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Efraim Reyes
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Luisa Carrillo
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
| | - Jose L. Vicario
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU); P.O. Box 644 48080 Bilbao Spain
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14
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Sunoj RB. Transition State Models for Understanding the Origin of Chiral Induction in Asymmetric Catalysis. Acc Chem Res 2016; 49:1019-28. [PMID: 27101013 DOI: 10.1021/acs.accounts.6b00053] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In asymmetric catalysis, a chiral catalyst bearing chiral center(s) is employed to impart chirality to developing stereogenic center(s). A rich and diverse set of chiral catalysts is now available in the repertoire of synthetic organic chemistry. The most recent trends point to the emergence of axially chiral catalysts based on binaphthyl motifs, in particular, BINOL-derived phosphoric acids and phosphoramidites. More fascinating ideas took shape in the form of cooperative multicatalysis wherein organo- and transition-metal catalysts are made to work in concert. At the heart of all such manifestations of asymmetric catalysis, classical or contemporary, is the stereodetermining transition state, which holds a perennial control over the stereochemical outcome of the catalytic process. Delving one step deeper, one would find that the origin of the stereoselectivity is delicately dependent on the relative stabilization of one transition state, responsible for the formation of the predominant stereoisomer, over the other transition state for the minor stereoisomer. The most frequently used working hypothesis to rationalize the experimentally observed stereoselectivity places an undue emphasis on steric factors and tends to regard the same as the origin of facial discrimination between the prochiral faces of the reacting partners. In light of the increasing number of asymmetric catalysts that rely on hydrogen bonding as well as other weak non-covalent interactions, it is important to take cognizance of the involvement of such interactions in the sterocontrolling transition states. Modern density functional theories offer a pragmatic and effective way to capture non-covalent interactions in transition states. Aided by the availability of such improved computational tools, it is quite timely that the molecular origin of stereoselectivity is subjected to more intelligible analysis. In this Account, we describe interesting molecular insights into the stereocontrolling transition states of five reaction types, three of which provide access to chiral quaternary carbon atoms. While each reaction has its own utility and interest, the focus of our research has been on the mechanism and the origin of the enantio- and diastereoselectivity. In all of the examples, such as asymmetric diamination, sulfoxidation, allylation, and Wacker-type ring expansion, the role played by non-covalent interactions in the stereocontrolling transition states has been identified as crucial. The transfer of the chiral information from the chiral catalyst to the product is identified as taking place through a series of non-covalent interactions between the catalyst and a given position/orientation of the substrate in the chiral environment offered by the axially chiral catalyst. The molecular insights enunciated herein allude to abundant opportunities for rational modifications of the present generation of catalysts and the choice of substrates in these as well as related families of reactions. It is our intent to propose that the domain of asymmetric catalysis could enjoy additional benefits by having knowledge of the vital stereoelectronic interactions in the stereocontrolling transition states.
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Affiliation(s)
- Raghavan B. Sunoj
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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15
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Bhaskararao B, Sunoj RB. Origin of Stereodivergence in Cooperative Asymmetric Catalysis with Simultaneous Involvement of Two Chiral Catalysts. J Am Chem Soc 2015; 137:15712-22. [DOI: 10.1021/jacs.5b05902] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Bangaru Bhaskararao
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Raghavan B. Sunoj
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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16
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Wagner JP, Schreiner PR. London’sche Dispersionswechselwirkungen in der Molekülchemie - eine Neubetrachtung sterischer Effekte. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201503476] [Citation(s) in RCA: 190] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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17
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Wagner JP, Schreiner PR. London dispersion in molecular chemistry--reconsidering steric effects. Angew Chem Int Ed Engl 2015; 54:12274-96. [PMID: 26262562 DOI: 10.1002/anie.201503476] [Citation(s) in RCA: 638] [Impact Index Per Article: 70.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Indexed: 12/15/2022]
Abstract
London dispersion, which constitutes the attractive part of the famous van der Waals potential, has long been underappreciated in molecular chemistry as an important element of structural stability, and thus affects chemical reactivity and catalysis. This negligence is due to the common notion that dispersion is weak, which is only true for one pair of interacting atoms. For increasingly larger structures, the overall dispersion contribution grows rapidly and can amount to tens of kcal mol(-1) . This Review collects and emphasizes the importance of inter- and intramolecular dispersion for molecules consisting mostly of first row atoms. The synergy of experiment and theory has now reached a stage where dispersion effects can be examined in fine detail. This forces us to reconsider our perception of steric hindrance and stereoelectronic effects. The quantitation of dispersion energy donors will improve our ability to design sophisticated molecular structures and much better catalysts.
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Affiliation(s)
- J Philipp Wagner
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, 35392 Giessen (Germany)
| | - Peter R Schreiner
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, 35392 Giessen (Germany).
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18
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Jindal G, Sunoj RB. Deciphering the Origin of Stereoinduction in Cooperative Asymmetric Catalysis Involving Pd(II) and a Chiral Brønsted Acid. Org Lett 2015; 17:2874-7. [PMID: 26057464 DOI: 10.1021/acs.orglett.5b00860] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The density functional (M06) computations on a cooperative multicatalytic reaction involving palladium acetate and a chiral Brønsted acid in the conversion of an indenyl cyclobutanol to spirocyclic indene bearing a quaternary carbon ring junction are reported. A chiral Pd-bis-phosphate is identified as the active catalyst in the enantioselective ring expansion as compared to alternative possibilities wherein the chiral phosphate/phosphoric acid is in the outer sphere of palladium. The enantiocontrolling transition state exhibited more effective C-H···π interactions, lower distortion of the catalyst, and an orthogonal orientation of the bulky phosphate ligands.
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Affiliation(s)
- Garima Jindal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Raghavan B Sunoj
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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19
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Krenske EH, Lam S, Ng JPL, Lo B, Lam SK, Chiu P, Houk KN. Concerted Ring Opening and Cycloaddition of Chiral Epoxy Enolsilanes with Dienes. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201503003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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20
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Krenske EH, Lam S, Ng JPL, Lo B, Lam SK, Chiu P, Houk KN. Concerted Ring Opening and Cycloaddition of Chiral Epoxy Enolsilanes with Dienes. Angew Chem Int Ed Engl 2015; 54:7422-5. [PMID: 25951012 DOI: 10.1002/anie.201503003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 11/11/2022]
Abstract
Silyl-triflate-catalyzed (4+3) cycloadditions of epoxy enolsilanes with dienes provide a mild and chemoselective synthetic route to seven-membered carbocycles. Epoxy enolsilanes containing a terminal enolsilane and a single stereocenter undergo cycloaddition with almost complete conservation of enantiomeric purity, a finding that argues against the involvement of oxyallyl cation intermediates which have been previously proposed for these types of reactions. Reported are theoretical and experimental investigations of the cycloaddition mechanism. The major enantiomers of the cycloadducts are derived from S(N)2-like reactions of the silylated epoxide with the diene, in which stereospecific ring opening and formation of the two new C-C bonds occur in a single step. Calculations predict, and experiments confirm, that the observed small losses of enantiomeric purity are traced to a triflate-mediated double S(N)2 cycloaddition pathway.
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Affiliation(s)
- Elizabeth H Krenske
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072 (Australia).
| | - Sarah Lam
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong (P. R. China)
| | - Jerome P L Ng
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong (P. R. China)
| | - Brian Lo
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong (P. R. China)
| | - Sze Kui Lam
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong (P. R. China)
| | - Pauline Chiu
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong (P. R. China).
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA).
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21
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Ma ZX, Patel A, Houk KN, Hsung RP. Highly torquoselective electrocyclizations and competing 1,7-hydrogen shifts of 1-azatrienes with silyl substitution at the allylic carbon. Org Lett 2015; 17:2138-41. [PMID: 25859907 DOI: 10.1021/acs.orglett.5b00727] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Highly torquoselective electrocyclizations of chiral 1-azatrienes are described. These 1-azatrienes contain an allylic stereocenter that is substituted with a silyl group and are derived in situ from condensation of γ-silyl-substituted enals with vinylogous amides. The ensuing stereoselective ring closures are part of a tandem sequence that constitutes an aza-[3 + 3] annulation method for constructing 1,2-dihydropyridines. Several mechanisms for the formal 1,7-hydrogen shift of these 1-azatrienes were evaluated computationally.
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Affiliation(s)
- Zhi-Xiong Ma
- †Division of Pharmaceutical Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
| | - Ashay Patel
- ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - K N Houk
- ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Richard P Hsung
- †Division of Pharmaceutical Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
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22
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Krenske EH, Houk KN, Harmata M. Computational analysis of the stereochemical outcome in the imidazolidinone-catalyzed enantioselective (4 + 3)-cycloaddition reaction. J Org Chem 2015; 80:744-50. [PMID: 25525966 DOI: 10.1021/jo501906m] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Computations show why the catalytic, asymmetric (4 + 3)-cycloaddition reaction developed in the Harmata laboratories proceeds with facial selectivity opposite to that for models proposed for related catalyzed Diels-Alder reactions. Computations with M06-2X/6-311+G(d,p)//B3LYP/6-31G(d) show that iminium ions derived from MacMillan's chiral 2-tert-butyl-5-benzylimidazolidinone and siloxypentadienals undergo (4 + 3)-cycloadditions with furans preferentially on the more crowded face. Conformational reorganization of the benzyl group, to avoid intramolecular interaction with the silyl group, is responsible for differentiating the activation barriers of top- and bottom-face attack.
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Affiliation(s)
- Elizabeth H Krenske
- School of Chemistry and Molecular Biosciences, University of Queensland , Brisbane, QLD 4072, Australia
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23
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Zhang YY, Hao J, Shi M. One pot cascade synthesis of fused heterocycles from furan-tethered terminal alkynes and aldehydes in the presence of amines and CuBr. Org Chem Front 2015. [DOI: 10.1039/c5qo00033e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel one-pot protocol for the construction of complex heterocycles through furan tethered terminal alkynes, aldehydes, amines and CuBr upon heating has been developed, giving the cycloadducts in moderate to high yields along with moderate to good regioselectivities.
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Affiliation(s)
- Yan-Yan Zhang
- Department of Chemistry
- Shanghai University
- Shanghai 200444
- China
| | - Jian Hao
- Department of Chemistry
- Shanghai University
- Shanghai 200444
- China
| | - Min Shi
- State Key Laboratory of Organometallic Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- China
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24
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Zhang J, Shao J, Xue J, Wang Y, Li Y. One pot hydroamination/[4 + 3] cycloaddition: synthesis towards the cyclohepta[b]indole core of silicine and ervatamine. RSC Adv 2014. [DOI: 10.1039/c4ra13249a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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25
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Slater NH, Brown NJ, Elsegood MRJ, Kimber MC. The Au(I) Catalyzed Activation of Allenamides and Their Subsequent Transformation into Chromanes: A Method for the Regiocontrolled Addition to the α- and γ-Positions of the Allene Unit. Org Lett 2014; 16:4606-9. [DOI: 10.1021/ol502178v] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Natasha H. Slater
- Department of Chemistry, Loughborough University, Leicestershire, LE11 3TU, U.K
| | - Natalie J. Brown
- Department of Chemistry, Loughborough University, Leicestershire, LE11 3TU, U.K
| | - Mark R. J. Elsegood
- Department of Chemistry, Loughborough University, Leicestershire, LE11 3TU, U.K
| | - Marc C. Kimber
- Department of Chemistry, Loughborough University, Leicestershire, LE11 3TU, U.K
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26
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Barnes KL, Koster AK, Jeffrey CS. Trapping the elusive aza-oxyallylic cation: new opportunities in heterocycloaddition chemistry. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.06.050] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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27
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He S, Hsung RP, Presser W, Ma ZX, Haugen BJ. An approach to cyclohepta[b]indoles through an allenamide (4 + 3) cycloaddition-Grignard cyclization-Chugaev elimination sequence. Org Lett 2014; 16:2180-3. [PMID: 24701990 PMCID: PMC3998770 DOI: 10.1021/ol5006455] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Indexed: 11/30/2022]
Abstract
A strategy for synthesizing highly functionalized cyclohepta[b]indoles through a concise (4 + 3) cycloaddition-cyclization-elimination sequence is described. The cycloaddition features nitrogen-stabilized oxyallyl cations derived from epoxidations of N-aryl-N-sulfonyl-substituted allenamides, while the cyclization and elimination employed an intramolecular Grignard addition and a one-step Chugaev process, respectively.
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Affiliation(s)
- Shuzhong He
- Division
of Pharmaceutical
Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
| | - Richard P. Hsung
- Division
of Pharmaceutical
Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
| | - William
R. Presser
- Division
of Pharmaceutical
Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
| | - Zhi-Xiong Ma
- Division
of Pharmaceutical
Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
| | - Bryan J. Haugen
- Division
of Pharmaceutical
Sciences, School of Pharmacy, and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, United States
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28
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Jindal G, Sunoj RB. Rational design of catalysts for asymmetric diamination reaction using transition state modeling. Org Biomol Chem 2014; 12:2745-53. [DOI: 10.1039/c3ob42520g] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
DFT calculations have been used to design chiral phosphoramidite ligands for the asymmetric diamination of vicinal diamines. The substituents at both the 3,3′ positions of the binol framework and the amido nitrogen play a vital role in the stereochemical outcome.
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Affiliation(s)
- Garima Jindal
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076, India
| | - Raghavan B. Sunoj
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076, India
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29
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Adams CS, Weatherly CD, Burke EG, Schomaker JM. The conversion of allenes to strained three-membered heterocycles. Chem Soc Rev 2014; 43:3136-63. [DOI: 10.1039/c3cs60416k] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The addition of heteroatoms to an allenic double bond yields strained heterocycles that serve as scaffolds for further useful transformations.
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Affiliation(s)
- C. S. Adams
- Department of Chemistry
- University of Wisconsin
- Madison, USA
| | | | - E. G. Burke
- Department of Chemistry
- University of Wisconsin
- Madison, USA
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30
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Fang LC, Hsung RP, Ma ZX, Presser WR. A highly stereoselective Diels-Alder cycloaddition of enones with chiral cyclic 2-amidodienes derived from allenamides. Org Lett 2013; 15:4842-5. [PMID: 24001055 DOI: 10.1021/ol402254p] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Lewis acid promoted Diels-Alder cycloadditions of a series of de novo chiral cyclic 2-amidodienes are described. These cyclic 2-amidodienes are derived from chiral α-allyl allenamides via a sequence of E-selective 1,3-H shift and 6π-electron pericyclic ring closure. With enones serving as effective dienophiles, these cycloadditions can be highly diastereoselective depending upon the chiral amide substituent, thereby representing a facile entry to optically enriched [2.2.2]bicyclic manifolds.
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Affiliation(s)
- Li-Chao Fang
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53705, United States
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31
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Lu T, Lu Z, Ma ZX, Zhang Y, Hsung RP. Allenamides: a powerful and versatile building block in organic synthesis. Chem Rev 2013; 113:4862-904. [PMID: 23550917 PMCID: PMC4539064 DOI: 10.1021/cr400015d] [Citation(s) in RCA: 272] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Ting Lu
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, WI 53705
| | - Zhenjie Lu
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, WI 53705
| | - Zhi-Xiong Ma
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, WI 53705
| | - Yu Zhang
- Discovery Research, Dow AgroSciences LLC, Indianapolis, IN 46268
| | - Richard P. Hsung
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, WI 53705
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32
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Priebbenow DL, Zou LH, Becker P, Bolm C. The Disubstitution of Acetals to Prepare δ,δ-Bis(aryl) β-Keto Esters. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300446] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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33
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Flynn BL, Manchala N, Krenske EH. Opposing Auxiliary Conformations Produce the Same Torquoselectivity in an Oxazolidinone-Directed Nazarov Cyclization. J Am Chem Soc 2013; 135:9156-63. [DOI: 10.1021/ja4036434] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bernard L. Flynn
- Medicinal Chemistry, Monash
Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Narasimhulu Manchala
- Medicinal Chemistry, Monash
Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Elizabeth H. Krenske
- School of Chemistry and Molecular
Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
- School of Chemistry, The University of Melbourne, VIC 3010, Australia
- Australian Research Council Centre of Excellence for Free Radical Chemistry and Biotechnology
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34
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Krenske EH, Houk KN. Aromatic interactions as control elements in stereoselective organic reactions. Acc Chem Res 2013; 46:979-89. [PMID: 22827883 PMCID: PMC3495095 DOI: 10.1021/ar3000794] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This Account describes how attractive interactions of aromatic rings with other groups can influence and control the stereoselectivity of many reactions. Recent developments in theory have improved the accuracy in the modeling of aromatic interactions. Quantum mechanical modeling can now provide insights into the roles of these interactions at a level of detail not previously accessible, both for ground-state species and for transition states of chemical reactions. In this Account, we show how transition-state modeling led to the discovery of the influence of aryl groups on the stereoselectivities of several types of organic reactions, including asymmetric dihydroxylations, transfer hydrogenations, hetero-Diels-Alder reactions, acyl transfers, and Claisen rearrangements. Our recent studies have also led to a novel mechanistic picture for two classes of (4 + 3) cycloadditions, both of which involve reactions of furans with oxyallyl intermediates. The first class of cycloadditions, developed by Hsung, features neutral oxyallyl intermediates that contain a chiral oxazolidinone auxiliary. Originally, it was thought that these cycloadditions relied on differential steric crowding of the two faces of a planar intermediate. Computations reveal a different picture and show that cycloaddition with furan takes place preferentially through the more crowded transition state: the furan adds on the same side as the Ph substituent of the oxazolidinone. The crowded transition state is stabilized by a CH-π interaction between furan and Ph worth approximately 2 kcal/mol. Attractive interactions with aromatic rings also control the stereoselectivity in a second class of (4+3) cycloadditions involving chiral alkoxy siloxyallyl cations. Alkoxy groups derived from chiral α-methylbenzyl alcohols favor crowded transition states, where a stabilizing CH-π interaction is present between the furan and the Ar group. The cationic cycloadditions are stepwise, while the Hsung cycloadditions are concerted. Our results suggest that this form of CH- π-directed stereocontrol is quite general and likely controls the stereoselectivities of other addition reactions in which one face of a planar intermediate bears a pendant aromatic substituent.
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Affiliation(s)
- Elizabeth H. Krenske
- School of Chemistry, University of Melbourne, VIC 3010, Australia, and Australian Research Council Centre of Excellence for Free Radical Chemistry and Biotechnology
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
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35
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Krenske EH, He S, Huang J, Du Y, Houk KN, Hsung RP. Intramolecular oxyallyl-carbonyl (3 + 2) cycloadditions. J Am Chem Soc 2013; 135:5242-5. [PMID: 23544997 PMCID: PMC3642281 DOI: 10.1021/ja312459b] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cycloadditions involving oxyallyl intermediates typically require an electron-rich diene or alkene, but we have discovered the first examples of the cycloaddition of heteroatom-stabilized oxyallyls onto carbonyl groups. An oxazolidinone-substituted oxyallyl undergoes chemoselective (3 + 2) cycloaddition onto the carbonyl group of a tethered dienone in preference to formation of the expected (4 + 3) cycloadduct. Density functional theory calculations indicated that the (3 + 2) cycloaddition takes place through a concerted, highly asynchronous mechanism. The transition state features simultaneous interactions of the oxyallyl LUMO with the carbonyl π and lone-pair orbitals, making this reaction "hemipseudopericyclic" (halfway between purely pericyclic and purely pseudopericyclic). Further (3 + 2) cycloadditions involving tethered phenyl ketones and a tethered enone were predicted theoretically and verified experimentally.
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Affiliation(s)
- Elizabeth H. Krenske
- School of Chemistry, The University of Melbourne, VIC 3010, Australia, and Australian Research Council Centre of Excellence for Free Radical Chemistry and Biotechnology
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Shuzhong He
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin at Madison, Madison, WI 53705
| | - Jian Huang
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin at Madison, Madison, WI 53705
| | - Yunfei Du
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin at Madison, Madison, WI 53705
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Richard P. Hsung
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin at Madison, Madison, WI 53705
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36
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Du Y, Krenske EH, Antoline JE, Lohse AG, Houk KN, Hsung RP. Control of regioselectivity and stereoselectivity in (4 + 3) cycloadditions of chiral oxyallyls with unsymmetrically disubstituted furans. J Org Chem 2013; 78:1753-9. [PMID: 22849303 DOI: 10.1021/jo3011792] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The regioselectivities and stereoselectivities of ZnCl2-catalyzed (4 + 3) cycloadditions between chiral oxazolidinone-substituted oxyallyls and unsymmetrical disubstituted furans have been determined. The substitution pattern on the furan is found to provide a valuable tool for controlling the stereochemistry (endo-I or endo-II) of the 7-membered cycloadduct. While cycloadditions with monosubstituted furans usually favor endo-I products, from addition of the furan to the more crowded face of the oxyallyl, cycloadditions with 2,3- and 2,5-disubstituted furans instead favor the endo-II stereochemistry. Density functional theory calculations are performed to account for the selectivities. For monosubstituted furans, the crowded transition state leading to the endo-I cycloadduct is stabilized by an edge-to-face interaction between the furan and the oxazolidinone 4-Ph group, but this stabilization is overcome by steric clashing if the furan bears a 2-CO2R group or is 2,3-disubstituted.
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Affiliation(s)
- Yunfei Du
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300072, PR China
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37
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Xu H, Zhang X, Ke ZF, Li ZF, Xu XY, Su CY, Phillips DL, Zhao C. Density functional theory study of the mechanism of zinc carbenoid promoted cyclopropanation of allenamides. RSC Adv 2013. [DOI: 10.1039/c3ra42168f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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38
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Krenske EH. Aromatic interactions in asymmetric catalysis: control of enantioselectivity in Diels–Alder reactions catalysed by camphor-derived hydrazides. Org Biomol Chem 2013; 11:5226-32. [DOI: 10.1039/c3ob40850g] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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39
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Lo B, Lam S, Wong WT, Chiu P. Asymmetric (4+3) Cycloadditions of Enantiomerically Enriched Epoxy Enolsilanes. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201207427] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Lo B, Lam S, Wong WT, Chiu P. Asymmetric (4+3) Cycloadditions of Enantiomerically Enriched Epoxy Enolsilanes. Angew Chem Int Ed Engl 2012; 51:12120-3. [DOI: 10.1002/anie.201207427] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Indexed: 11/06/2022]
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41
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Krenske EH. Origins of Aryl Substituent Effects on the Stereoselectivities of Additions of Silyl Enol Ethers to a Chiral Oxazolinium Ion. Org Lett 2011; 13:6572-5. [DOI: 10.1021/ol202911v] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elizabeth H. Krenske
- School of Chemistry, University of Melbourne, Victoria 3010, Australia, and Australian Research Council Centre of Excellence for Free Radical Chemistry and Biotechnology
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42
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Winne JM, Catak S, Waroquier M, Van Speybroeck V. Scope and Mechanism of the (4+3) Cycloaddition Reaction of Furfuryl Cations. Angew Chem Int Ed Engl 2011; 50:11990-3. [DOI: 10.1002/anie.201104930] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Indexed: 11/12/2022]
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43
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Winne JM, Catak S, Waroquier M, Van Speybroeck V. Scope and Mechanism of the (4+3) Cycloaddition Reaction of Furfuryl Cations. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201104930] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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44
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Antoline JE, Krenske EH, Lohse AG, Houk KN, Hsung RP. Stereoselectivities and regioselectivities of (4 + 3) cycloadditions between allenamide-derived chiral oxazolidinone-stabilized oxyallyls and furans: experiment and theory. J Am Chem Soc 2011; 133:14443-51. [PMID: 21851070 DOI: 10.1021/ja205700p] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A systematic investigation of the regioselectivities and stereoselectivities of (4 + 3) cycloadditions between unsymmetrical furans and a chiral oxazolidinone-substituted oxyallyl is presented. Cycloadditions were performed using an oxyallyl containing a (R)-4-phenyl-2-oxazolidinone auxiliary (2(Ph)), under either thermal or ZnCl(2)-catalyzed conditions. Reactions of 2(Ph) with 2-substituted furans gave syn cycloadducts selectively, while cycloadditions with 3-substituted furans gave selectively anti cycloadducts. The stereoselectivities were in favor of a single diastereoisomer (I) in all but one case (2-CO(2)R). Density functional theory calculations were performed to explain the selectivities. The results support a mechanism in which all cycloadducts are formed from the E isomer of the oxyallyl (in which the oxazolidinone C═O and oxyallyl oxygen are anti to each other) or the corresponding (E)-ZnCl(2) complex. The major diastereomer is derived from addition of the furan to the more crowded face of the oxyallyl. Crowded transition states are favored because they possess a stabilizing CH-π interaction between the furan and the Ph group.
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Affiliation(s)
- Jennifer E Antoline
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, USA
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45
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Duarte FJS, Bakalova SM, Cabrita EJ, Gil Santos A. Lewis Acid Catalyzed Reactions of Chiral Imidazolidinones and Oxazolidinones: Insights on the Role of the Catalyst. J Org Chem 2011; 76:6997-7004. [DOI: 10.1021/jo201318f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Filipe J. S. Duarte
- REQUIMTE, CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Snezhana M. Bakalova
- REQUIMTE, CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
- Institute of Organic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev str., block 9, 1113 Sofia, Bulgaria
| | - Eurico J. Cabrita
- REQUIMTE, CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - A. Gil Santos
- REQUIMTE, CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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46
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Feltenberger JB, Hsung RP. Oppolzer-type intramolecular Diels-Alder cycloadditions via isomerizations of allenamides. Org Lett 2011; 13:3114-7. [PMID: 21612235 PMCID: PMC3112474 DOI: 10.1021/ol2010227] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A new approach to Oppolzer's intramolecular Diels-Alder cycloaddition (IMDA) through γ-isomerization of readily available N-tethered allenamides is described. These IMDA reactions are carried out in tandem with the allenamide isomerization or 1,3-H shift, leading to complex nitrogen heterocycles in a highly stereoselective manner.
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Affiliation(s)
- John B. Feltenberger
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, WI 53705
| | - Richard P. Hsung
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, WI 53705
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47
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Lohse AG, Hsung RP, Leider MD, Ghosh SK. Developing a diastereoselective intramolecular [4+3] cycloaddition of nitrogen-stabilized oxyallyl cations derived from N-sulfonyl-substituted allenamides. J Org Chem 2011; 76:3246-57. [PMID: 21449577 PMCID: PMC3095656 DOI: 10.1021/jo200147h] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Efforts toward achieving a practical and diastereoselective intramolecular [4+3] cycloaddition of nitrogen-stabilized oxyallyl cations with tethered dienes are described. Epoxidation of N-sulfonyl substituted allenamides with dimethyldioxirane (DMDO) generates nitrogen-stabilized oxyallyl cations that readily undergo stereoselective [4+3] cycloaddition with dienes. Selectivity is found to depend on the tethering length as well as the stability of the oxyallyl cation intermediate, whether generated from N-carbamoyl- or N-sulfonyl-substituted allenamides. The use of chiral N-sulfonyl-substituted allenamides provided minimal diastereoselectivity in the cycloaddition, while high diastereoselectivity can be achieved with a stereocenter present on the tether. These studies provide further support for the synthetic utility of allenamides.
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Affiliation(s)
- Andrew G. Lohse
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, WI 53705
| | - Richard P. Hsung
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, WI 53705
| | - Mitchell D. Leider
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, WI 53705
| | - Sunil K. Ghosh
- Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, WI 53705
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48
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Jeffrey CS, Barnes KL, Eickhoff JA, Carson CR. Generation and Reactivity of Aza-Oxyallyl Cationic Intermediates: Aza-[4 + 3] Cycloaddition Reactions for Heterocycle Synthesis. J Am Chem Soc 2011; 133:7688-91. [DOI: 10.1021/ja201901d] [Citation(s) in RCA: 159] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Korry L. Barnes
- Department of Chemistry, University of Nevada—Reno, Reno, Nevada 89557, United States
| | - John A. Eickhoff
- Department of Chemistry, University of Nevada—Reno, Reno, Nevada 89557, United States
| | - Christopher R. Carson
- Department of Chemistry, University of Nevada—Reno, Reno, Nevada 89557, United States
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49
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Hayashi R, Feltenberger JB, Lohse AG, Walton MC, Hsung RP. An efficient and practical entry to 2-amido-dienes and 3-amido-trienes from allenamides through stereoselective 1,3-hydrogen shifts. Beilstein J Org Chem 2011; 7:410-20. [PMID: 21512601 PMCID: PMC3079123 DOI: 10.3762/bjoc.7.53] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Accepted: 03/16/2011] [Indexed: 12/16/2022] Open
Abstract
Preparations of de novo acyclic 2-amido-dienes and 3-amido-trienes through 1,3-hydrogen shifts from allenamides are described. These 1,3-hydrogen shifts could be achieved thermally or they could be promoted by the use of Brønsted acids. Under either condition, these processes are highly regioselective in favour of the α-position, and highly stereoselective in favour of the E-configuration. In addition, 6π-electron electrocyclic ring-closure could be carried out with 3-amido-trienes to afford cyclic 2-amido-dienes, and such electrocyclic ring-closure could be rendered in tandem with the 1,3-hydrogen shift.
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Affiliation(s)
- Ryuji Hayashi
- Department of Chemistry and Division of Pharmaceutical Sciences, University of Wisconsin, Madison, WI 53705
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50
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Lohse AG, Hsung RP. (4+3) cycloaddition reactions of nitrogen-stabilized oxyallyl cations. Chemistry 2011; 17:3812-22. [PMID: 21384451 DOI: 10.1002/chem.201100260] [Citation(s) in RCA: 191] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The use of heteroatom-substituted oxyallyl cations in (4+3) cycloadditions has had a tremendous impact on the development of cycloaddition chemistry. Extensive efforts have been exerted toward investigating the effect of oxygen, sulfur, and halogen substituents on the reactivity of oxyallyl cations. Most recently, the use of nitrogen-stabilized oxyallyl cations has gained prominence in the area of (4+3) cycloadditions. The following article will provide an overview of this concept utilizing nitrogen-stabilized oxyallyl cations.
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Affiliation(s)
- Andrew G Lohse
- Division of Pharmaceutical Sciences, Department of Chemistry, University of Wisconsin, Madison, Madison, WI 53705, USA
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