Continuous Flow Synthesis of Cyclobutenes Using LED Technology

    • Megan Smytha
    • Thomas S Moodya,b
    • Scott Wharrya
    • Marcus Baumannc
    • aBiocatalysis group, Almac Sciences Ltd, Craigavon, United Kingdom of Great Britain and Northern Ireland
    • bManufacturing, Arran Chemical Company, Athlone, Ireland
    • bChemistry, University of Durham, Durham, United Kingdom of Great Britain and Northern Ireland

    Cyclobutenes are highly strained ring systems of considerable synthetic interest that can be accessed via cycloaddition reactions between alkenes and alkynes. However, their traditional preparation relies on photochemical [2+2]-cycloadditions that exploit low wavelength UV radiation emitted from inefficient medium-pressure Hg-lamps. This paper reports on the development of a modern approach using a high-power LED set-up emitting at the boundary of UV-A and visible light in conjunction with a continuous flow reactor. The resulting flow process renders a series of cyclobutenes from maleimides and various commercial alkynes. This provides a more energy-efficient approach that is readily scalable to access multigram quantities of cyclobutenes in high chemical yields and short residence times. The value of these products is exemplified by flow-based hydrogenations yielding highly substituted cyclobutanes which represent sought after building blocks in modern medicinal chemistry programs.

    Read the publication that featured this abstract

    Get in touch

    For more information on flow chemistry systems and services please use the contact methods below.

    Call us on +44 (0)1284 728659 or Email us