Application of the anionic homologous Fries‐rearrangement to the synthesis of 3‐alkylbenzofuran‐2(3H)‐ones |
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Authors: | Ugo Azzena Luisa Pisano Mario Pittalis |
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Affiliation: | Dipartimento di Chimica, Università di Sassari, via Vienna 2, I‐07100 Sassari, Italy |
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Abstract: | We have developed an effective organometallic‐based procedure allowing the employment of 2‐methylphenols as easily available starting materials in the synthesis of 3‐alkylbenzofuran‐2(3H)‐ones. The first step of this protocol, an anionic homologous Fries‐rearrangement, afforded 2‐(2‐ tert ‐butyldimethylsilyloxyaryl)acetamides, which were selectively metalated and monoalkylated at the benzylic position. Acidic work‐up of crude products afforded the desired heterocycles in satisfactory overall yields. Copyright © 2008 John Wiley & Sons, Ltd. |
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Keywords: | alkylation benzofuran‐2(3H)‐ones Fries rearrangement metalation organolithiums regioselectivity |
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