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Unusual (3 THF)-microsolvated dimers and donor-free aggregates of two lithium enolates. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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2
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Oiarbide M, Palomo C. Extended Enolates: Versatile Intermediates for Asymmetric C-H Functionalization via Noncovalent Catalysis. Chemistry 2021; 27:10226-10246. [PMID: 33961323 PMCID: PMC8361983 DOI: 10.1002/chem.202100756] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Indexed: 12/22/2022]
Abstract
Catalyst-controlled functionalization of unmodified carbonyl compounds is a relevant operation in organic synthesis, especially when high levels of site- and stereoselectivity can be attained. This objective is now within reach for some subsets of enolizable substrates using various types of activation mechanisms. Recent contributions to this area include enantioselective transformations that proceed via transiently generated noncovalent di(tri)enolate-catalyst coordination species. While relatively easier to form than simple enolate congeners, di(tri)enolates are ambifunctional in nature and so control of the reaction regioselectivity becomes an issue. This Minireview discusses in some detail this and other problems, and how noncovalent activation approaches based on metallic and metal free catalysts have been developed to advance the field.
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Affiliation(s)
- Mikel Oiarbide
- Departamento de Química Orgánica IUniversidad del País Vasco UPV/EHUManuel Lardizabal 320018San SebastiánSpain
| | - Claudio Palomo
- Departamento de Química Orgánica IUniversidad del País Vasco UPV/EHUManuel Lardizabal 320018San SebastiánSpain
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3
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Influence of counterion on the methylation of some ambident nucleophiles: DFT study. REACTION KINETICS MECHANISMS AND CATALYSIS 2018. [DOI: 10.1007/s11144-017-1263-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Stabbert R, Dempsey R, Diekmann J, Euchenhofer C, Hagemeister T, Haussmann HJ, Knorr A, Mueller BP, Pospisil P, Reininghaus W, Roemer E, Tewes FJ, Veltel DJ. Studies on the contributions of smoke constituents, individually and in mixtures, in a range of in vitro bioactivity assays. Toxicol In Vitro 2017; 42:222-246. [PMID: 28461234 DOI: 10.1016/j.tiv.2017.04.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 04/03/2017] [Accepted: 04/04/2017] [Indexed: 01/21/2023]
Abstract
Tobacco smoke is a complex mixture with over 8700 identified constituents. Smoking causes many diseases including lung cancer, cardiovascular disease, and chronic obstructive pulmonary disease. However, the mechanisms of how cigarette smoke impacts disease initiation or progression are not well understood and individual smoke constituents causing these effects are not generally agreed upon. The studies reported here were part of a series of investigations into the contributions of selected smoke constituents to the biological activity of cigarette smoke. In vitro cytotoxicity measured by the neutral red uptake (NRU) assay and in vitro mutagenicity determined in the Ames bacterial mutagenicity assay (BMA) were selected because these assays are known to produce reproducible, quantitative results for cigarette smoke under standardized exposure conditions. In order to determine the contribution of individual cigarette smoke constituents, a fingerprinting method was developed to semi-quantify the mainstream smoke yields. For cytotoxicity, 90% of gas vapor phase (GVP) cytotoxicity of the Kentucky Reference cigarette 1R4F was explained by 3 aldehydes and 40% of the 1R4F particulate phase cytotoxicity by 10 smoke constituents, e.g., hydroquinone. In the microsuspension version of the BMA, 4 aldehydes accounted for approximately 70% of the GVP mutagenicity. Finally, the benefits of performing such studies along with the difficulties in interpretation in the context of smoking are discussed.
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Affiliation(s)
- Regina Stabbert
- Philip Morris Products SA, Philip Morris International R&D, Rue des Usines 90, CH-2000 Neuchatel, Switzerland.
| | - Ruth Dempsey
- Philip Morris Products SA, Philip Morris International R&D, Rue des Usines 90, CH-2000 Neuchatel, Switzerland
| | - Joerg Diekmann
- Philip Morris Research Laboratories GmbH, Fuggerstrasse 3, D-51149 Cologne, Germany
| | | | - Timo Hagemeister
- Philip Morris Research Laboratories GmbH, Fuggerstrasse 3, D-51149 Cologne, Germany
| | | | - Arno Knorr
- Philip Morris Products SA, Philip Morris International R&D, Quai Jeanrenaud 5, CH-2000, Neuchatel, Switzerland
| | - Boris P Mueller
- Philip Morris Research Laboratories GmbH, Fuggerstrasse 3, D-51149 Cologne, Germany
| | - Pavel Pospisil
- Philip Morris Products SA, Philip Morris International R&D, Quai Jeanrenaud 5, CH-2000, Neuchatel, Switzerland
| | - Wolf Reininghaus
- Philip Morris Research Laboratories GmbH, Fuggerstrasse 3, D-51149 Cologne, Germany
| | - Ewald Roemer
- Philip Morris Products SA, Philip Morris International R&D, Rue des Usines 90, CH-2000 Neuchatel, Switzerland
| | - Franz J Tewes
- Philip Morris Research Laboratories GmbH, Fuggerstrasse 3, D-51149 Cologne, Germany
| | - Detlef J Veltel
- Philip Morris Research Laboratories GmbH, Fuggerstrasse 3, D-51149 Cologne, Germany
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Iriarte I, Olaizola O, Vera S, Gamboa I, Oiarbide M, Palomo C. Controlling the α/γ-Reactivity of Vinylogous Ketone Enolates in Organocatalytic Enantioselective Michael Reactions. Angew Chem Int Ed Engl 2017; 56:8860-8864. [DOI: 10.1002/anie.201703764] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 05/13/2017] [Indexed: 12/12/2022]
Affiliation(s)
- Igor Iriarte
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Olatz Olaizola
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Silvia Vera
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Iñaki Gamboa
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Mikel Oiarbide
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Claudio Palomo
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
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6
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Iriarte I, Olaizola O, Vera S, Gamboa I, Oiarbide M, Palomo C. Controlling the α/γ-Reactivity of Vinylogous Ketone Enolates in Organocatalytic Enantioselective Michael Reactions. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201703764] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Igor Iriarte
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Olatz Olaizola
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Silvia Vera
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Iñaki Gamboa
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Mikel Oiarbide
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
| | - Claudio Palomo
- Departamento de Química Orgánica I; Universidad del País Vasco UPV/EHU; Manuel Lardizabal 3 20018 San Sebastián Spain
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Chen X, Tan Y, Berionni G, Ofial AR, Mayr H. Di- and Triarylmethylium Ions as Probes for the Ambident Reactivities of Carbanions Derived from 5-Benzylated Meldrum’s Acid. Chemistry 2014; 20:11069-77. [DOI: 10.1002/chem.201403161] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Indexed: 11/08/2022]
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9
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Pereshivko OP, Peshkov VA, Jacobs J, Meervelt LV, Van der Eycken EV. Cationic Gold- and Silver-Catalyzed Cycloisomerizations of Propargylic Ureas: A Selective Entry to Oxazolidin-2-imines and Imidazolidin-2-ones. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201200905] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Mayr H, Breugst M, Ofial AR. Farewell to the HSAB treatment of ambident reactivity. Angew Chem Int Ed Engl 2011; 50:6470-505. [PMID: 21726020 DOI: 10.1002/anie.201007100] [Citation(s) in RCA: 208] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Indexed: 11/11/2022]
Abstract
The concept of hard and soft acids and bases (HSAB) proved to be useful for rationalizing stability constants of metal complexes. Its application to organic reactions, particularly ambident reactivity, has led to exotic blossoms. By attempting to rationalize all the observed regioselectivities by favorable soft-soft and hard-hard as well as unfavorable hard-soft interactions, older treatments of ambident reactivity, which correctly differentiated between thermodynamic and kinetic control as well as between different coordination states of ionic substrates, have been replaced. By ignoring conflicting experimental results and even referring to untraceable experimental data, the HSAB treatment of ambident reactivity has gained undeserved popularity. In this Review we demonstrate that the HSAB as well as the related Klopman-Salem model do not even correctly predict the behavior of the prototypes of ambident nucleophiles and, therefore, are rather misleading instead of useful guides. An alternative treatment of ambident reactivity based on Marcus theory will be presented.
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Affiliation(s)
- Herbert Mayr
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13 (Haus F), 81377 München, Germany.
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11
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Gräting R, Brandsma L. Preliminary Communications: Chemistry of 2H-thiopyran and derivatives V. Regiospecific methylation and protonation of the di-anion, obtained from reductive cleavage of 2H-thiopyran. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19790981008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Breugst M, Zipse H, Guthrie J, Mayr H. Marcus Analysis of Ambident Reactivity. Angew Chem Int Ed Engl 2010; 49:5165-9. [DOI: 10.1002/anie.201001574] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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15
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16
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Oare DA, Heathcock CH. Stereochemistry of the Base-Promoted Michael Addition Reaction. TOPICS IN STEREOCHEMISTRY 2007. [DOI: 10.1002/9780470147283.ch5] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Braunstein P, Siri O, Taquet JP, Yang QZ. Regioselective Carbon–Carbon Bond Formation Reactions between TCNE or TCNQ and a Quinonoid Ring. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200502574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Braunstein P, Siri O, Taquet JP, Yang QZ. Regioselective Carbon–Carbon Bond Formation Reactions between TCNE or TCNQ and a Quinonoid Ring. Angew Chem Int Ed Engl 2006; 45:1393-7. [PMID: 16425336 DOI: 10.1002/anie.200502574] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Pierre Braunstein
- Laboratoire de Chimie de Coordination, Institut de Chimie, UMR 7177 CNRS, Université Louis Pasteur, 4 Rue Blaise Pascal, 67070 Strasbourg Cedex, France.
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20
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Anders E, Korn U, Stankowiak A. „Ferngesteuerte”︁ nucleophile Eigenschaften der Anionen einiger 4‐Alkylpyridine: AM 1‐ und MNDO‐Berechnungen sowie experimentelle Untersuchungen. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cber.19891220117] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ernst Anders
- Institut für Organische Chemie der Universität Erlangen‐Nürnberg, Henkestraße 42, D‐8520 Erlangen
| | - Uwe Korn
- Institut für Organische Chemie der Universität Erlangen‐Nürnberg, Henkestraße 42, D‐8520 Erlangen
| | - Achim Stankowiak
- Institut für Organische Chemie der Universität Erlangen‐Nürnberg, Henkestraße 42, D‐8520 Erlangen
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21
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Tochtermann W, Gustmann H, Wolff C. Stickstoffheterocyclen, 1: Zur Reaktion von Bis(5‐tetrazolyl)‐disulfiden mit Diazoalkanen. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cber.19781110216] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Werner Tochtermann
- Institut für Organische Chemie der Universität Kiel, Olshausenstr. 40/60, D‐2300 Kiel
| | - Hartmut Gustmann
- Institut für Organische Chemie der Universität Kiel, Olshausenstr. 40/60, D‐2300 Kiel
| | - Christian Wolff
- Institut für Organische Chemie der Universität Kiel, Olshausenstr. 40/60, D‐2300 Kiel
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22
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Anders E, Will W, Gaßner T. Zur Acylierbarkeit von Carbonylverbindungen mittels 1‐Acylpyridiniumsalzen. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cber.19831160426] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ernst Anders
- Institut für Organische Chemie der Universität Erlangen‐Nürnberg, Henkestr. 42, D‐8520 Erlangen
| | - Wolfgang Will
- Institut für Organische Chemie der Universität Erlangen‐Nürnberg, Henkestr. 42, D‐8520 Erlangen
| | - Thomas Gaßner
- Institut für Organische Chemie der Universität Erlangen‐Nürnberg, Henkestr. 42, D‐8520 Erlangen
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23
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Schroth W, Kluge H, Frach R, Hodek W, Schädler HD. Zur Dehydratisierung von Harnstoffen mit Dichlorcarben im Phasentransfer-Verfahren, ein Zugang zu substituierten Cyanamiden. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/prac.19833250512] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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24
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Kunz W, Kristinsson H. Bildung von 4-, 5- und 6gliedrigen Heterocyclen durch ambidoselektive Ringschlüsse von Enolat-Ionen. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19790620326] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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25
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Ansorge M, Polborn K, Müller TJ. Synthesis and structure of the chromiumcarbonyl complexed phenyl allene. J Organomet Chem 2001. [DOI: 10.1016/s0022-328x(01)00867-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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Abstract
3-Oxo-17 alpha-pregna-4,6-diene-21,17-carbolactone (canrenone, II) is produced from the potassium salt of 17-hydroxy-3-oxo-17 alpha-pregna-4,6-diene-21-carboxylic acid (I) by acid catalyzed lactonization. II reacts with acetic anhydride/nitric acid to give one main product (III) and some minor products. The structure of III was determined by chemical and spectral analysis to the 4-nitro derivative of canrenone. This result is in contrast to the known reactions of II with most other reagents that were found to add at delta(6), and also in contrast to the reactions of acetic anhydride/nitric acid with alkenes. Electrophilic substitution at the ambident C4 is discussed as the reaction path. The 4-nitro group enhances the inhibitory activity of II against Na+/K(+)-ATPase, the target enzyme of the cardioactive digitalis glycosides, which appears to indicate increased cardioactivity.
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Affiliation(s)
- R Megges
- Max-Delbrück-Center for Molecular Medicine, Berlin-Buch, Germany
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27
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Ahlbrecht H, Kramer A. Chiral Homoenolate Equivalents, V. Hydroxylakylation of Lithiated 3-[(S)-2-(Methoxymethyl)pyrrolidino]-1,3-diphenylpropene – An Asymmetric Homoaldol Reaction. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/cber.19961291004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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28
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Substituierte 2-Alkoxy-5-amino- und-2,5-diamino-imidazole aus Oxazol-2-yliden-cyanamiden. MONATSHEFTE FUR CHEMIE 1996. [DOI: 10.1007/bf00813797] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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29
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30
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Limat D, Schlosser M. The selective O-acylation of enolates providing a simple entry to O-enesters. Tetrahedron 1995. [DOI: 10.1016/0040-4020(95)00250-c] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Hünig S, Schäfer M. Trimethylsilylcyanid als Umpolungsreagens, XX. Zur Regioselektivität der Addition von Carbonyl-;Verbindungen an umgepolte α,β-ungesättigte Aldehyde. ACTA ACUST UNITED AC 1993. [DOI: 10.1002/cber.19931260126] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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Freriks IL, de Koning LJ, Nibbering NM. Gas-phase ambident reactivity of imidate anions (−NR1(CO)R2). ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0168-1176(92)80102-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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33
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Gewald K, Sch�fer H, Bellmann P, Hain U. Zur Synthese von 3-Amino-pyrrolen durch Thorpe-Ziegler-Cyclisierung. ACTA ACUST UNITED AC 1992. [DOI: 10.1002/prac.19923340608] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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34
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The synthesis of N-substituted ureas I: The N-alkylation of ureas. MONATSHEFTE FUR CHEMIE 1992. [DOI: 10.1007/bf00816855] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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35
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36
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Unger C, Zimmer R, Reißig HU, Würthwein EU. Deprotonation of 5,6-Dihydro-5-methylene-4H-1,2-oxazines and Regioselective Reactions with Electrophiles. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/cber.19911241021] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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37
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Reißig HU, Hippeli C. Lithiated 5,6-Dihydro-4H-1,2-oxazines: Synthesis, Highly Diastereoselective Reactions with Electrophiles, and Subsequent Transformations. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/cber.19911240120] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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38
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J�ger L, K�hler H. Pseudochalkogenverbindungen. XXV. Phenoxy-cyanamidoacetate M[C6H5OCH2?C(O)NCN] (M = Li, Na, K, Cs, Ag) - Darstellung und Methylierung. Z Anorg Allg Chem 1990. [DOI: 10.1002/zaac.19905880108] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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39
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Gompper R, Wagner HU. Donor-acceptor-substituierte cyclische π-Elektronensysteme - Prüfsteine für Theorien und Bausteine für neue Materialien. Angew Chem Int Ed Engl 1988. [DOI: 10.1002/ange.19881001105] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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40
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Heuschmann M. Mehrstufige inverse Diels-Alder-Reaktionen von 1,3-Dimethyl-2-methylenimidazolidin mit 2,4-Hexadiensäure-methylestern. ACTA ACUST UNITED AC 1988. [DOI: 10.1002/cber.19881210108] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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41
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42
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K�hler H, Glanz D. Pseudochalkogenverbindungen. XIV. Die Synthese von Trimethylcyanamidophosphaten, ein Beitrag zur Ambivalenz der Cyanamidophosphat-lonen, [PO4?n(NCN)n]3? Z Anorg Allg Chem 1987. [DOI: 10.1002/zaac.19875541116] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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43
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Feith B, Weber HM, Maas G. Dikationether, 11. Ambidoselektive Reaktionen von β-Ketoenolaten mit Dikationethern. European J Org Chem 1986. [DOI: 10.1002/jlac.198619861207] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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Hünig S, Reichelt H. Trimethylsilylcyanid als Umpolungsreagens, XI. Über den ambidenten Charakter substituierter Allyl-Anionen. ACTA ACUST UNITED AC 1986. [DOI: 10.1002/cber.19861190604] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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45
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Steric control of regiochemistry in the reactions of methyl substituted pentadienyl cations with isobutene. Tetrahedron 1986. [DOI: 10.1016/s0040-4020(01)82104-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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46
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Schroth W. Aspects and prospects of the chemistry of organic heterocycles (review). Part II. Chem Heterocycl Compd (N Y) 1985. [DOI: 10.1007/bf00842954] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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