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Synlett 2020; 31(19): 1942-1946
DOI: 10.1055/s-0040-1705945
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Integrated Synthesis Using Continuous-Flow Technologies

Subsupercritical Water Generated by Inductive Heating Inside Flow Reactors Facilitates the Claisen Rearrangement

Mona Oltmanns
,
Andreas Kirschning  ∗
Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
› Author AffiliationsThis work was supported in part by the Symrise AG, Holzminden, Germany.
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Abstract

Claisen rearrangement of electron-deficient O-allylated phenols, including fluorine-modified phenols, is facilitated in aqueous media at high temperatures and pressures under flow conditions, as opposed to organic solvents. The O-allylation of phenols can be coupled with the Claisen rearrangement in an integrated flow system.

Key words

Claisen rearrangement - flow chemistry - fluorobenzenes - inductive heating - supercritical water

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0040-1705945. Included are experimental procedures, spectral data and copies of 1H and 13C NMR spectra of all new compounds and intermediates.
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Publication History

Received: 14 August 2020

Accepted after revision: 16 September 2020

Article published online:
27 October 2020

© 2020. Thieme. All rights reserved

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