Synthesis of 2,3-Dihydrobenzofurans via the Palladium Catalyzed Carboalkoxylation of 2-Allylphenols.

A new Pd-catalyzed alkene carboalkoxylation strategy for the preparation of 2,3-dihydrobenzofurans is described. This method effects the coupling of readily available 2-allylphenol derivatives with aryl triflates to generate a wide range of functionalized 2,3-dihydrobenzofurans in good yields and diastereoselectivities (up to >20:1). Use of newly developed reaction conditions that promote anti-heteropalladation of the alkene is essential in order to generate products in high yield.