Remarkable Electronic Effect on the Diastereoselectivity of the Heck Reaction of Methyl Cinnamate with Arenediazonium Salts: Formal Total Synthesis of (±)-Indatraline and (±)-Sertraline



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An efficient and stereoselective protocol for the preparation of β,β-disubstituted acrylates in good to high yields by means of a Heck–Matsuda arylation was accomplished. The method employs a base- and ligand-free Heck arylation reaction of methyl cinnamate using both electron-deficient and electron-rich arenediazonium salts as electrophiles. The Heck reaction displays a remarkable electronic dependence regarding the diastereoselectivity of the arylation process, which correlates with the electronic nature of the arenediazonium salts employed. A rationale for the observed diastereoselectivity is presented. The overall methodology provides a convenient route to 3-arylindanones and 4-aryltetralones allowing the concise formal total syntheses of the therapeutically important psychoactive compounds (±)-indatraline and (±)-sertraline.