A valuable Lewis-acid-catalysed domino reaction involving a Friedel–Crafts alkylation of variously substituted phenols followed by a direct lactonization has been successfully developed (22 examples, yields up to 98?%). This protocol tolerates not only opposite electron demand substituents on the starting materials, but also drastic modifications of the alkylating agents, and gives direct access to the corresponding 3-hydroxy-benzofuran-2-ones, which could easily undergo further chemical transformation. The relevance of our method was further confirmed by the straightforward synthesis of rac-BHFF, the recently discovered and extremely promising positive allosteric modulator of the GABAB receptor.
Gasperi, T., Vetica, F., Pelosi, A., Gambacorta, A., LORETO M., A., Miceli, M. (2014). Catalytic Friedel-Crafts/Lactonization Domino Reaction: Facile Access to 3-Hydroxybenzofuran-2-one Scaffold. EUROPEAN JOURNAL OF ORGANIC CHEMISTRY [10.1002/ejoc.201301686].
Catalytic Friedel-Crafts/Lactonization Domino Reaction: Facile Access to 3-Hydroxybenzofuran-2-one Scaffold
GASPERI, TECLA;GAMBACORTA, Augusto;
2014-01-01
Abstract
A valuable Lewis-acid-catalysed domino reaction involving a Friedel–Crafts alkylation of variously substituted phenols followed by a direct lactonization has been successfully developed (22 examples, yields up to 98?%). This protocol tolerates not only opposite electron demand substituents on the starting materials, but also drastic modifications of the alkylating agents, and gives direct access to the corresponding 3-hydroxy-benzofuran-2-ones, which could easily undergo further chemical transformation. The relevance of our method was further confirmed by the straightforward synthesis of rac-BHFF, the recently discovered and extremely promising positive allosteric modulator of the GABAB receptor.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
