Regioselective synthesis of 5-ethoxycarbonyl-, 5-acetyl- and 5-trifluoroacetyl-6-trifluoromethylsalicylates by one-pot cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-alkoxy-2-alken-1-ones

5-Ethoxycarbonyl-, 5-trifluoroacetyl-, and 5-acetyl-6-trifluoromethylsalicylates were prepared by one-pot cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-alkoxy-2-alken-1-ones. The reactions proceeded with very good regioselectivity by conjugate addition of the terminal carbon atom of the diene to the enone and subsequent cyclization. The cyclization proceeded in most cases via the trifluoroacetyl group.

Graphical abstract5-Ethoxycarbonyl-, 5-acetyl- and 5-trifluoroacetyl-6-trifluoromethylsalicylates were efficiently prepared by one-pot cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-alkoxy-2-alken-1-ones.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Trifluorinated arenes were prepared by a one-pot procedure. ► The products are not readily available by other methods. ► The reactions proceed with very good regioselectivity.