A versatile and regiospecific synthesis of functionalized 1,3-diarylisobenzofurans
Jérôme Jacq1, Cathy Einhorn, Jacques Einhorn
1Département de Chimie Moléculaire (SERCO), UMR-5250, ICMG FR-2607, Université Joseph Fourier, 301 Rue de la Chimie, BP 53, 38041 Grenoble Cedex 9, France.
Abstract:
A convenient, versatile, and regiospecific synthesis of functionalized 1,3-diarylisobenzofurans has been developed. It involves chemoselective addition of arylmagnesium reagents to the aldehyde function of o-aroylbenzaldehydes, themselves readily obtained by lead tetraacetate oxidation of N-aroylhydrazones of salicylaldehydes. Various functional groups, including nitro, iodo, or ester functionalities, have thus been positioned with complete regiospecificity on the 1,3-diphenylisobenzofuran backbone.
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