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  1. Article ; Online: Biocatalytic Enantioselective Synthesis of Atropisomers.

    Watts, Olivia F B / Berreur, Jordan / Collins, Beatrice S L / Clayden, Jonathan

    Accounts of chemical research

    2022  Volume 55, Issue 23, Page(s) 3362–3375

    Abstract: ConspectusAtropisomeric compounds are found extensively as natural products, as ligands for asymmetric transition-metal catalysis, and increasingly as bioactive and pharmaceutically relevant targets. Their enantioselective synthesis is therefore an ... ...

    Abstract ConspectusAtropisomeric compounds are found extensively as natural products, as ligands for asymmetric transition-metal catalysis, and increasingly as bioactive and pharmaceutically relevant targets. Their enantioselective synthesis is therefore an important ongoing research target. While a vast majority of known atropisomeric structures are (hetero)biaryls, which display hindered rotation around a C-C single bond, our group's long-standing interest in the control of molecular conformation has led to the identification and stereoselective preparation of a variety of other classes of "nonbiaryl" atropisomeric compounds displaying restricted rotation around C-C, C-N, C-O, and C-S single bonds.Biocatalytic transformations are finding increasing application in both academic and industrial contexts as a result of a significant broadening of the range of biocatalytic reactions and sources of enzymes available to the synthetic chemist. In this Account, we summarize the main biocatalytic strategies currently available for the asymmetric synthesis of biaryl, heterobiaryl, and nonbiaryl atropisomers. As is the case with more traditional synthetic approaches to these compounds, most biocatalytic methodologies for the construction of enantioenriched atropisomers follow one of two distinct strategies. The first of these is the direct asymmetric construction of atropisomeric bonds. Synthetically applicable biocatalytic methodologies for this type of transformation are limited, despite the extensive research into the biosynthesis of (hetero)biaryls by oxidative homocoupling or cross-coupling of electron-rich arenes. The second of these is the asymmetric transformation of a molecule in which the bond that will form the axis already exists, and this approach represents the majority of biocatalytic strategies available to the synthetic organic chemist. This strategy encompasses a variety of stereoselective techniques including kinetic resolution (KR), desymmetrization, dynamic kinetic resolution (DKR), and dynamic kinetic asymmetric transformation (DYKAT).Nondynamic kinetic resolution (KR) of conformationally stable biaryl derivatives has provided the earliest and most numerous examples of synthetically useful methodologies for the enantioselective preparation of atropisomeric compounds. Lipases (i.e., enzymes that mediate the formation or hydrolysis of esters) are particularly effective and have attracted broad attention. This success has led researchers to broaden the scope of lipase-mediated transformations to desymmetrization reactions, in addition to a limited number of DKR and DYKAT examples. By contrast, our group has used redox enzymes, including an engineered galactose oxidase (GOase) and commercially available ketoreductases (KREDs), to desymmetrize prochiral atropisomeric diaryl ether and biaryl derivatives. Building on this experience and our long-standing interest in dynamic conformational processes, we later harnessed intramolecular noncovalent interactions to facilitate bond rotation at ambient temperatures, which allowed the development of the efficient DKR of heterobiaryl aldehydes using KREDs. With this Account we provide an overview of the current and prospective biocatalytic strategies available to the synthetic organic chemist for the enantioselective preparation of atropisomeric molecules.
    MeSH term(s) Stereoisomerism ; Prospective Studies ; Biocatalysis ; Molecular Conformation ; Catalysis
    Language English
    Publishing date 2022-11-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1483291-4
    ISSN 1520-4898 ; 0001-4842
    ISSN (online) 1520-4898
    ISSN 0001-4842
    DOI 10.1021/acs.accounts.2c00572
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  2. Article ; Online: Corrigendum: How Big is the Pinacol Boronic Ester as a Substituent?

    Fasano, Valerio / McFord, Aidan W / Butts, Craig P / Collins, Beatrice S L / Fey, Natalie / Alder, Roger W / Aggarwal, Varinder K

    Angewandte Chemie (International ed. in English)

    2021  Volume 60, Issue 37, Page(s) 20087

    Language English
    Publishing date 2021-08-29
    Publishing country Germany
    Document type Published Erratum
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202106534
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Dynamic Responsive Systems for Catalytic Function.

    Vlatković, Matea / Collins, Beatrice S L / Feringa, Ben L

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2016  Volume 22, Issue 48, Page(s) 17080–17111

    Abstract: Responsive systems have recently gained much interest in the scientific community in attempts to mimic dynamic functions in biological systems. One of the fascinating potential applications of responsive systems lies in catalysis. Inspired by nature, ... ...

    Abstract Responsive systems have recently gained much interest in the scientific community in attempts to mimic dynamic functions in biological systems. One of the fascinating potential applications of responsive systems lies in catalysis. Inspired by nature, novel responsive catalytic systems have been built that show analogy with allosteric regulation of enzymes. The design of responsive catalytic systems allows control of catalytic activity and selectivity. In this Review, advances in the field over the last four decades are discussed and a comparison is made amongst the dynamic responsive systems based on the principles underlying their catalytic mechanisms. The catalyst systems are sorted according to the triggers used to achieve control of the catalytic activity and the distinct catalytic reactions illustrated.
    Language English
    Publishing date 2016-09-15
    Publishing country Germany
    Document type Review ; Journal Article
    ZDB-ID 1478547-X
    ISSN 1521-3765 ; 0947-6539
    ISSN (online) 1521-3765
    ISSN 0947-6539
    DOI 10.1002/chem.201602453
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: How Big is the Pinacol Boronic Ester as a Substituent?

    Fasano, Valerio / McFord, Aidan W / Butts, Craig P / Collins, Beatrice S L / Fey, Natalie / Alder, Roger W / Aggarwal, Varinder K

    Angewandte Chemie (International ed. in English)

    2020  Volume 59, Issue 50, Page(s) 22403–22407

    Abstract: The synthetically versatile pinacol boronic ester group (Bpin) is generally thought of as a bulky moiety because of the two adjacent quaternary ... ...

    Abstract The synthetically versatile pinacol boronic ester group (Bpin) is generally thought of as a bulky moiety because of the two adjacent quaternary sp
    Language English
    Publishing date 2020-10-07
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202007776
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Enantiospecific Synthesis of ortho-Substituted 1,1-Diarylalkanes by a 1,2-Metalate Rearrangement/anti-S

    Rubial, Belén / Collins, Beatrice S L / Bigler, Raphael / Aichhorn, Stefan / Noble, Adam / Aggarwal, Varinder K

    Angewandte Chemie (International ed. in English)

    2018  Volume 58, Issue 5, Page(s) 1366–1370

    Abstract: The one-pot sequential coupling of benzylamines, boronic esters, and aryl iodides has been investigated. In the presence of an N-activator, the boronate complex formed from an ortho-lithiated benzylamine and a boronic ester undergoes stereospecific 1,2- ... ...

    Abstract The one-pot sequential coupling of benzylamines, boronic esters, and aryl iodides has been investigated. In the presence of an N-activator, the boronate complex formed from an ortho-lithiated benzylamine and a boronic ester undergoes stereospecific 1,2-metalate rearrangement/anti-S
    Language English
    Publishing date 2018-12-21
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.201811343
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Copper-catalyzed arylative Meyer-Schuster rearrangement of propargylic alcohols to complex enones using diaryliodonium salts.

    Collins, Beatrice S L / Suero, Marcos G / Gaunt, Matthew J

    Angewandte Chemie (International ed. in English)

    2013  Volume 52, Issue 22, Page(s) 5799–5802

    Language English
    Publishing date 2013-05-27
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.201301529
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  7. Article ; Online: Asymmetric Synthesis of Secondary and Tertiary Boronic Esters.

    Collins, Beatrice S L / Wilson, Claire M / Myers, Eddie L / Aggarwal, Varinder K

    Angewandte Chemie (International ed. in English)

    2017  Volume 56, Issue 39, Page(s) 11700–11733

    Abstract: Non-racemic chiral boronic esters are recognised as immensely valuable building blocks in modern organic synthesis. Their stereospecific transformation into a variety of functional groups-from amines and halides to arenes and alkynes-along with their air ...

    Abstract Non-racemic chiral boronic esters are recognised as immensely valuable building blocks in modern organic synthesis. Their stereospecific transformation into a variety of functional groups-from amines and halides to arenes and alkynes-along with their air and moisture stability, has established them as an important target for asymmetric synthesis. Efforts towards the stereoselective synthesis of secondary and tertiary alkyl boronic esters have spanned over five decades and are underpinned by a wealth of reactivity platforms, drawing on the unique and varied reactivity of boron. This Review summarizes strategies for the asymmetric synthesis of alkyl boronic esters, from the seminal hydroboration methods of H. C. Brown to the current state of the art.
    Language English
    Publishing date 2017-08-09
    Publishing country Germany
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.201701963
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Bifunctional Molecular Photoswitches Based on Overcrowded Alkenes for Dynamic Control of Catalytic Activity in Michael Addition Reactions.

    Pizzolato, Stefano F / Collins, Beatrice S L / van Leeuwen, Thomas / Feringa, Ben L

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2017  Volume 23, Issue 25, Page(s) 6174–6184

    Abstract: The emerging field of artificial photoswitchable catalysis has recently shown striking examples of functional light-responsive systems allowing for dynamic control of activity and selectivity in organocatalysis and metal-catalysed transformations. While ... ...

    Abstract The emerging field of artificial photoswitchable catalysis has recently shown striking examples of functional light-responsive systems allowing for dynamic control of activity and selectivity in organocatalysis and metal-catalysed transformations. While our group has already disclosed systems featuring first generation molecular motors as the switchable central core, a design based on second generation molecular motors is lacking. Here, the syntheses of two bifunctionalised molecular switches based on a photoresponsive tetrasubstituted alkene core are reported. They feature a thiourea substituent as hydrogen-donor moiety in the upper half and a basic dimethylamine group in the lower half. This combination of functional groups offers the possibility for application of these molecules in photoswitchable catalytic processes. The light-responsive central cores were synthesized by a Barton-Kellogg coupling of the prefunctionalized upper and lower halves. Derivatization using Buchwald-Hartwig amination and subsequent introduction of the thiourea substituent afforded the target compounds. Control of catalytic activity in the Michael addition reaction between (E)-3-bromo-β-nitrostyrene and 2,4-pentanedione is achieved upon irradiation of stable-(E) and stable-(Z) isomers of the bifunctional catalyst 1. Both isomers display a decrease in catalytic activity upon irradiation to the metastable state, providing systems with the potential to be applied as ON/OFF catalytic photoswitches.
    Language English
    Publishing date 2017-01-04
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1478547-X
    ISSN 1521-3765 ; 0947-6539
    ISSN (online) 1521-3765
    ISSN 0947-6539
    DOI 10.1002/chem.201604966
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  9. Article ; Online: Enantioselective Rhodium(III)-Catalyzed Markovnikov Hydroboration of Unactivated Terminal Alkenes.

    Smith, James R / Collins, Beatrice S L / Hesse, Matthew J / Graham, Mark A / Myers, Eddie L / Aggarwal, Varinder K

    Journal of the American Chemical Society

    2017  Volume 139, Issue 27, Page(s) 9148–9151

    Abstract: We report the first enantioselective Rh-catalyzed Markovnikov hydroboration of unactivated terminal alkenes. Using a novel ... ...

    Abstract We report the first enantioselective Rh-catalyzed Markovnikov hydroboration of unactivated terminal alkenes. Using a novel sp
    Language English
    Publishing date 2017-06-30
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.7b05149
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Enantioselective Rhodium(III)-Catalyzed Markovnikov Hydroboration of Unactivated Terminal Alkenes

    Smith, JamesR / Aggarwal Varinder K / Collins Beatrice S. L / Graham Mark A / Hesse Matthew J / Myers Eddie L

    Journal of the American Chemical Society. 2017 July 12, v. 139, no. 27

    2017  

    Abstract: We report the first enantioselective Rh-catalyzed Markovnikov hydroboration of unactivated terminal alkenes. Using a novel sp2–sp3 hybridized diboron reagent and water as a proton source, a broad range of alkenes undergo hydroboration to provide ... ...

    Abstract We report the first enantioselective Rh-catalyzed Markovnikov hydroboration of unactivated terminal alkenes. Using a novel sp2–sp3 hybridized diboron reagent and water as a proton source, a broad range of alkenes undergo hydroboration to provide secondary boronic esters with high regio- and enantiocontrol.
    Keywords alkenes ; boron compounds ; enantioselectivity ; esters ; rhodium
    Language English
    Dates of publication 2017-0712
    Size p. 9148-9151.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021%2Fjacs.7b05149
    Database NAL-Catalogue (AGRICOLA)

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