Organic letters

Palladium-Catalyzed Synthesis of 4-Oxaspiro [2.4] heptanes via Central Attack of Oxygen Nucleophiles to π-Allylpalladium Intermediates

R Shintani, T Ito, T Hayashi

Index: Shintani, Ryo; Ito, Tomoaki; Hayashi, Tamio Organic Letters, 2012 , vol. 14, # 9 p. 2410 - 2413

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Citation Number: 8

Abstract

A palladium-catalyzed decarboxylative cyclopropanation of γ-methylidene-δ-valerolactones with aromatic aldehydes has been developed to give 4-oxaspiro [2.4] heptanes with high selectivity. The site of nucleophilic attack to a π-allylpalladium intermediate has been controlled with a sterically demanding phosphine ligand. The course of the reaction is highly dependent on ligands and solvents, and selective formation of methylenetetrahydropyrans ...