Synthesis 2021; 53(11): 1911-1922
DOI: 10.1055/s-0040-1706006
paper

Sequencing Groebke–Blackburn–Bienaymé and Aza-Michael Addition Reactions: A Modular Strategy for Accessing a Diverse Collection of Constrained Benzoxazepine and Imidazopyrazine Systems

Authors

  • Vunnam Srinivasulu

    a   Sharjah Institute for Medical Research, University of Sharjah, 27272, Sharjah, UAE
  • Farah Al-Marzooq

    d   Department of Medical Microbiology and Immunology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE
  • Mohamad Hamad

    a   Sharjah Institute for Medical Research, University of Sharjah, 27272, Sharjah, UAE
    b   College of Health Sciences, University of Sharjah, 27272, Sharjah, UAE
  • Monther A. Khanfar

    a   Sharjah Institute for Medical Research, University of Sharjah, 27272, Sharjah, UAE
    e   Department of Chemistry, University of Jordan, 11942, Amman, Jordan
  • Mani Ramanathan

    f   Department of Biology, Chemistry and Environmental Sciences, American University of Sharjah, 26666, Sharjah, UAE
  • Nelson C. Soares

    a   Sharjah Institute for Medical Research, University of Sharjah, 27272, Sharjah, UAE
    c   College of Pharmacy, University of Sharjah, 27272, Sharjah, UAE
  • Taleb H. Al-Tel

    a   Sharjah Institute for Medical Research, University of Sharjah, 27272, Sharjah, UAE
    c   College of Pharmacy, University of Sharjah, 27272, Sharjah, UAE

This work was supported by generous grants from the Islamic Development Bank (IsDB), Transform Fund (Grant No. 2018-2021) and the Research Funding Department, University of Sharjah, UAE (Grant No. 1801110125-P).


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Abstract

We present a divergent strategy that permits access to diversely functionalized benzoxazepinium scaffolds fused to various heterocycles. The described strategy features a one-pot combination of the Groebke–Blackburn–Bienaymé reaction and an aza-Michael addition. Methyl (E)-4-(2-formylphenoxy)but-2-enoate and its derivatives are utilized as central elements in this cascade. These building blocks are reacted with a variety of functionalized amino-azines and tert-butyl isocyanide under ytterbium triflate [Yb(OTf)3] catalysis. The ensuing cascade represents a rapid, modular and atom-economic process that leads to the construction of a diverse collection of constrained benzoxazepinium systems from a wide substrate scope.

Supporting Information



Publikationsverlauf

Eingereicht: 01. Oktober 2020

Angenommen nach Revision: 07. Dezember 2020

Artikel online veröffentlicht:
07. Januar 2021

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