Selective functionalization of norbornadiene through nitrile oxide cycloaddition/ring‐opening/cross‐metathesis protocols

This work presents an examination of the selective functionalization of norbornadiene through nitrile oxide 1,3-dipolar cycloaddition/ring-opening metathesis (ROM)/cross-metathesis (CM) protocols. Functionalization of commercially available norbornadiene provided novel bicyclic scaffolds with multiple stereogenic centers. The synthesis involved selective cycloadditions, with subsequent ROM of the formed cycloalkene-fused isoxazoline scaffolds and selective CM by chemodifferentiation of the olefin bonds of the resulting alkenylated derivatives. Various experimental conditions were applied for the CM transformations with the goal of exploring substrate and steric effects, catalyst influence and chemodifferentiation of the olefin bonds furnishing the corresponding functionalized, fluorine-containing isoxazoline derivatives.

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Diversity-Oriented Synthesis of Highly Functionalized Alicycles across Dipolar Cycloaddition/Metathesis Reaction

Synlett ◽

10.1055/s-0040-1706041 ◽

2021 ◽

Author(s):

Loránd Kiss ◽

Zsanett Benke ◽

Melinda Nonn ◽

Attila M. Remete ◽

Santos Fustero

Keyword(s):

Amino Acid ◽

Ring Opening ◽

Nitrile Oxide ◽

Amino Acid Derivatives ◽

Selective Synthesis ◽

Chemical Transformations ◽

Bond Functionalization ◽

Cross Metathesis ◽

Chlorosulfonyl Isocyanate ◽

Biological Potential

AbstractThis Account gives an insight into the selective functionalization of some readily available commercial cyclodienes across simple chemical transformations into functionalized small-molecular scaffolds. The syntheses involved selective cycloadditions, followed by ring-opening metathesis (ROM) of the resulting azetidin-2-one derivatives or isoxazoline frameworks and selective cross metathesis (CM) by discrimination of the C=C bonds on the alkenylated heterocycles. The CM protocols have been described when investigated under various conditions with the purpose on exploring chemodifferentiation of the olefin bonds and a study on the access of the corresponding functionalized β-lactam or isoxazoline derivatives is presented. Due to the expanding importance of organofluorine chemistry in drug research as well as of the high biological potential of β-lactam derivatives several illustrative examples to the access of some fluorine-containing molecular entities is also presented in this synopsis.1 Introduction2 Ring C=C Bond Functionalization of Some Cycloalkene β-Amino Acid Derivatives across Chlorosulfonyl Isocyanate Cycloaddition3 Ring C=C Bond Functionalization of Some Cycloalkene β-Amino Acid Derivatives across Nitrile Oxide Cycloaddition4 Ring C=C Bond Functionalization of Some Cycloalkene β-Amino Acid Derivatives across Metathesis5 Functionalization of sSome Cyclodienes across Nitrile Oxide Cycloaddition6 Selective Synthesis of Functionalized Alicycles across Ring-Opening Metathesis7 Selective Synthesis of Functionalized Alicycles through Cross Metathesis8 Summary and Outlook9 List of Abbreviations

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Endgroup and Sidechain Functionalization of Surface-Initiated ROMP Thin Films: Progress Towards ROMP-Based Molecular Wires

10.26434/chemrxiv.5954518 ◽

2018 ◽

Author(s):

Nicholas Marshall

Keyword(s):

Thin Films ◽

Contact Angle ◽

Cyclic Voltammetry ◽

Polymer Films ◽

Conjugated Polymer ◽

Ring Opening ◽

Molecular Wires ◽

Metathesis Polymerization ◽

Cross Metathesis ◽

Active Ester

A set of experiments in surface-initiated ring-opening metathesis polymerization, including end-functionalization of growing brushes and contact angle/cyclic voltammetry measurements. We report preparation and CV of two different conjugated polymer films, and several endgroup and sidechain functionalization experiments using cross-metathesis and active ester substitution.<br>

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