Enantiopure 4-oxazolin-2-ones and 4-methylene-2-oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles

Blanca M. Santoyo, Carlos González-Romero, Daniel Zárate-Zárate, R. Israel Hernández-Benitez, Vanessa Pelayo, Edson Barrera, Carlos H. Escalante, Aydeé Fuentes-Benites, Guadalupe Martínez-Morales, Julio López, Miguel A. Vázquez, Francisco Delgado, Hugo A. Jiménez-Vázquez, Joaquín Tamariz

    Research output: Contribution to journalArticlepeer-review

    2 Scopus citations

    Abstract

    Enantiopure 3-((R)- and 3-((S)-1-phenylethyl)-4-oxazoline-2-ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N-(R)- or N-(S)-1-phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric induction of the 4- and 5-positions of the 4-oxazolin-2-one ring through thermal and MW-promoted nucleophilic conjugated addition to Michael acceptors and alkyl halides. The resulting adducts were transformed via a cascade process into fused six-membered carbo- and heterocycles. The structure of the reaction products depended on the electrophiles and reaction conditions used. Alternative isomeric 4-methylene-2-oxazolidinones served as chiral precursors for a versatile and divergent approach to highly substituted cyclic carbamates. DFT quantum calculations showed that the formation of bicyclic pyranyl compounds was generated by a diastereoselective concerted hetero-Diels-Alder cycloaddition.

    Original languageEnglish
    Pages (from-to)719-749
    Number of pages31
    JournalChirality
    Volume31
    Issue number9
    DOIs
    StatePublished - 1 Jan 2019

    Keywords

    • (R)- and (S)-1-phenylethylamine
    • 4-methylene-2-oxazolidinones
    • 4-oxazolin-2-ones
    • hetero-Diels-Alder reaction
    • microwave irradiation

    Fingerprint

    Dive into the research topics of 'Enantiopure 4-oxazolin-2-ones and 4-methylene-2-oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles'. Together they form a unique fingerprint.

    Cite this