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Synthesis of alkenyl boronates from allyl-substituted aromatics using an olefin cross-metathesis protocol
Rémy Hemelaere1, François Carreaux, Bertrand Carboni
1Sciences Chimiques de Rennes, UMR 6226 CNRS- Université de Rennes 1, 263, Avenue du Général Leclerc, Campus de Beaulieu, Bâtiment 10A, 35042 Rennes Cedex, France.
Abstract:
An efficient synthesis of 3-aryl-1-propenyl boronates from pinacol vinyl boronic ester and allyl-substituted aromatics by cross metathesis is reported. Although the allylbenzene derivatives are prone to isomerization reaction under metathesis conditions, we found that some ruthenium catalysts are effective for this methodology. This strategy thus provides an interesting alternative approach to alkyne hydroboration, leading to the preparation of unknown compounds. Moreover, the boron substituent can be replaced by various functional groups in good yields.
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