Catalytic multi-step continuous-flow processes for scalable transformation of eugenol into potential fragrances

    • Fábio M.S. Rodriguesa
    • Vitaliy Masliya
    • Madalena F.C. Silvaa
    • Alexandre P. Felgueirasa
    • Rui M.B. Carrilhoa
    • Mariette M. Pereiraa
    • aUniversity of Coimbra, Coimbra Chemistry Centre, Department of Chemistry, Rua Larga, 3004-535 Coimbra, Portugal

    Catalytic multi-step processes were optimized and developed under continuous-flow conditions, to transform eugenol into potential new fragrances. One approach consisted in the direct catalytic conversion of eugenyl acetate into the corresponding cyclic carbonate, through a two-step protocol that utilizes two different tubular flow reactors for Mn(V)-catalysed epoxidation, using imidazole as co-catalyst and hydrogen peroxide as the oxidant, followed by the epoxide carboxylation with carbon dioxide, catalysed by a binary ZnBr2/TBAB catalytic system. With this methodology, a productivity of 7.68 g product per day was obtained. The other approach is an efficient hydroformylation/acetalization sequential process, which operates through a multi-stage flow system consisting of a tubular reactor for the Rh(I)/xantphos-catalysed hydroformylation, coupled in series with a K10 packed bed reactor for the aldehyde acetalization step. This pioneering strategy allowed obtaining 94 % chemoselectivity for acetal formation and 96 % regioselectivity for the linear product, resulting in a process productivity of 10.02 g product per day.

    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