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    ChemInform Abstract: Conjugate Addition of Imidazolines: A Protocol for 1,4‐Addition to Enones and Other Acceptors.
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    Abstract The methyleneimidazolidines (I) react with the electron‐deficient olefins (II) to give the adducts (III) which are hydrolyzed and decarboxylated to form the imidazolidines (IV).
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    Conjugate
    Addition reaction
    The authors present an enantio­selective intermolecular crossed-conjugate addition of nitroalkenes and α,β-unsaturated aldehydes through a dual Lewis base (LB) activation strategy. In the presence of 20 mol% of the prolinol catalyst, the crossed-conjugate addition proceeded smoothly with the addition of (OMe)3P and AcOH, providing the adducts in good yields and high enantioselectivities. A synthetic application was demonstrated by the authors, in which the crossed-conjugate addition product 4 was transformed into the only trans-­isomer of substituted pyrrolidine 5.
    Conjugate
    Pyrrolidine
    Addition reaction
    Base (topology)
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    Chelation between γ-hydroxy unsaturated nitriles and Grignard reagents promotes an otherwise difficult anionic conjugate addition reaction. The intermediate chelate is readily generated by deprotonation with t-BuMgCl followed by the addition of a second Grignard reagent that triggers an intramolecular conjugate addition. Structurally diverse Grignard reagents add with equal efficiency, providing an intermediate anion that stereoselectively alkylates BnBr in an overall addition−alkylation reaction.
    Conjugate
    Addition reaction
    Grignard reagent
    Grignard reaction
    Citations (28)
    Conjugate addition reactions of aldehydes to nitroolefins provide synthetically useful ?-nitroaldehydes. Here we summarize our research on peptide-catalyzed conjugate addition reactions of aldehydes to differently substituted nitroolefins. We show that peptides of the general type Pro-Pro-Xaa (Xaa = acidic amino acid) are not only highly active, robust and stereoselective catalysts but have also remarkable chemoselectivities.
    Conjugate
    Addition reaction
    Citations (6)
    Conjugate
    Addition reaction
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    This chapter contains sections titled: Introduction Additions to Aldehydes and Ketones Additions to Imines and Iminium Ions Additions to Carboxylic Acids and Their Derivatives Conjugate Addition to α,β-Unsaturated Carbonyl Compounds Synthesis of Heterocycles References
    Iminium
    Conjugate
    Addition reaction
    Carbonyl group
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    The conjugate addition reaction has been a useful tool in the formation of carbon–carbon bonds. The utility of this reaction has been demonstrated in the synthesis of many natural products, materials, and pharmacological agents. In the last three decades, there has been a significant increase in the development of asymmetric variants of this reaction. Unfortunately, conjugate addition reactions using α,β-unsaturated amides and lactams remain underdeveloped due to their inherently low reactivity. This review highlights the work that has been done on both diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams.
    Conjugate
    Reactivity
    Addition reaction
    Citations (58)
    This chapter contains sections titled: Introduction Conjugate Reaction of α,β-Unsaturated Ketones, Amides, and Nitriles Conjugate Addition of Nitroalkenes Conjugate Addition of Vinyl Sulfones and Vinyl Phosphates Cyclopropanation and Other Related Reactions Conclusions References
    Conjugate
    Addition reaction
    Nucleophilic Addition
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