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  1. Article: A Novel, Stereocontrolled Synthesis of 1,2-trans-Cyclopropanes: Cyclopropyl Boronate Esters as Partners in Suzuki Couplings with Aryl Halides

    Hildebrand, Jens P. / Marsden, Stephen P.

    Synlett

    1996  Volume 1996, Issue 09, Page(s) 893–894

    Keywords cyclopropane ; palladium ; Suzuki ; cyclopropyl boronate
    Language English
    Publishing date 1996-01-01
    Publishing place Stuttgart ; New York
    Document type Article
    ZDB-ID 2042012-2
    ISSN 1437-2096 ; 0936-5214
    ISSN (online) 1437-2096
    ISSN 0936-5214
    DOI 10.1055/s-1996-5608
    Database Thieme publisher's database

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  2. Article ; Online: Catalyzed Asymmetric Arylation Reactions.

    Bolm, Carsten / Hildebrand, Jens P. / Muñiz, Kilian / Hermanns, Nina

    Angewandte Chemie (International ed. in English)

    2000  Volume 40, Issue 18, Page(s) 3284–3308

    Abstract: Addition and substitution reactions with carbon nucleophiles are fundamental processes in organic synthesis, and the development of general catalytic asymmetric variants thereof is still a major challenge today. In contrast to enantioselective alkyl ... ...

    Abstract Addition and substitution reactions with carbon nucleophiles are fundamental processes in organic synthesis, and the development of general catalytic asymmetric variants thereof is still a major challenge today. In contrast to enantioselective alkyl transfer reactions, the corresponding arylations have not yet reached a high level of maturity. The existing protocols are either of no general applicability or are limited in terms of selectivity. This article summarizes established routes for catalytic asymmetric aryl transfer together with the latest developments in this area. The scope and limitations of this reaction are discussed.
    Language English
    Publishing date 2000-11-16
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/1521-3773(20010917)40:18<3284::aid-anie3284>3.0.co;2-u
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Catalytic Coupling of Aryl Sulfonates with sp2-Hybridized Nitrogen Nucleophiles: Palladium- and Nickel-catalyzed Synthesis of N-Aryl Sulfoximines

    Bolm, Carsten / Hildebrand, Jens P. / Rudolph, Jens

    Synthesis

    2000  Volume 2000, Issue 07, Page(s) 911–913

    Keywords palladium ; nickel ; sulfoximines ; cross-coupling ; aryl sulfonates
    Language English
    Publishing date 2000-01-01
    Publishing place Stuttgart ; New York
    Document type Article
    ZDB-ID 2033062-5
    ISSN 1437-210X ; 0039-7881
    ISSN (online) 1437-210X
    ISSN 0039-7881
    DOI 10.1055/s-2000-6287
    Database Thieme publisher's database

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  4. Article ; Online: Application of a Planar Chiral eta(5)-Cyclopentadienylrhenium(I)tricarbonyl Complex in Asymmetric Catalysis: Highly Enantioselective Phenyl Transfer to Aldehydes We are grateful to the Deutsche Forschungsgemeinschaft (DFG) within the Collaborative Research Center (SFB) 380 "Asymmetric Synthesis by Chemical and Biological Methods" and the Fonds der Chemischen Industrie for financial support and to Dr. C. W. Lehmann, MPI für Kohlenforschung, Mülheim, for collecting the X-ray diffraction data. M.K. acknowledges the DFG for a predoctoral fellowship (Graduiertenkolleg). We thank Degussa and Witco for donations of chemicals and Professor Dr. A. Salzer as well as Dipl.-Ing. M. Treu for inspiring discussions. We also appreciate the stimulus of Dr. K. Muñiz for the investigation of the influence of the metal-pi-fragment on catalyses of this type.

    Bolm, Carsten / Kesselgruber, Martin / Hermanns, Nina / Hildebrand, Jens P. / Raabe, Gerhard

    Angewandte Chemie (International ed. in English)

    2001  Volume 40, Issue 8, Page(s) 1488–1490

    Language English
    Publishing date 2001-04-17
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Application of a Planar Chiral η

    Bolm, Carsten / Kesselgruber, Martin / Hermanns, Nina / Hildebrand, Jens P / Raabe, Gerhard

    Angewandte Chemie (International ed. in English)

    2001  Volume 40, Issue 8, Page(s) 1488–1490

    Abstract: A novel planar chiral cyrhetrene 1 has been identified as an efficient catalyst precursor for the asymmetric synthesis of diarylmethanol compounds 2 by phenylation of aldehydes. Compared to the corresponding ferrocene derivative, the performance of the ... ...

    Abstract A novel planar chiral cyrhetrene 1 has been identified as an efficient catalyst precursor for the asymmetric synthesis of diarylmethanol compounds 2 by phenylation of aldehydes. Compared to the corresponding ferrocene derivative, the performance of the cyrhetrene is superior or at least equally as good and gives excellent enantioselectivities even with catalyst loadings as low as 2 mol %.
    Language English
    Publishing date 2001-04-17
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/1521-3773(20010417)40:8<1488::AID-ANIE1488>3.0.CO;2-B
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Structural investigation of high-valent manganese-salen complexes by UV/Vis, Raman, XANES, and EXAFS spectroscopy.

    Feth, Martin P / Bolm, Carsten / Hildebrand, Jens P / Köhler, Manuela / Beckmann, Oliver / Bauer, Matthias / Ramamonjisoa, Rivo / Bertagnolli, Helmut

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2003  Volume 9, Issue 6, Page(s) 1348–1359

    Abstract: XANES and EXAFS spectroscopic studies at the Mn-K- and Br-K-edge of reaction products of (S,S)-(+)-N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III) chloride ([(salen)Mn(III)Cl], 1) and (S,S)-(+)-N,N'-bis(3,5-di-tert- ... ...

    Abstract XANES and EXAFS spectroscopic studies at the Mn-K- and Br-K-edge of reaction products of (S,S)-(+)-N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III) chloride ([(salen)Mn(III)Cl], 1) and (S,S)-(+)-N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III) bromide ([(salen)Mn(III)Br], 2) with 4-phenylpyridine N-oxide (4-PPNO) and 3-chloroperoxybenzoic acid (MCPBA) are reported. The reaction of the Mn(III) complexes with two equivalents of 4-PPNO leads to a hexacoordinated compound, in which the manganese atom is octahedrally coordinated by four oxygen/nitrogen atoms of the salen ligand at an average distance of approximately 1.90 A and two additional, axially bonded oxygen atoms of the 4-PPNO at 2.25 A. The oxidation state of this complex was determined as approximately +IV by a comparative study of Mn(III) and Mn(V) reference compounds. The green intermediate obtained in reactions of MCPBA and solutions of 1 or 2 in acetonitrile was investigated with XANES, EXAFS, UV/Vis, and Raman spectroscopy, and an increase of the coordination number of the manganese atoms from 4 to 5 and the complete abstraction of the halide was observed. A formal oxidation state of IV was deduced from the relative position of the pre-edge 1s-->3d feature of the X-ray absorption spectrum of the complex. The broad UV/Vis band of this complex in acetonitrile with lambda(max)=648 nm was consistent with a radical cation structure, in which a MCPBA molecule was bound to the Mn(IV) central atom. An oxomanganese(V) or a dimeric manganese(IV) species was not detected.
    Language English
    Publishing date 2003-03-17
    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.200390154
    Database MEDical Literature Analysis and Retrieval System OnLINE

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