An Improvement of the Palladium-Catalyzed [4+2] Cycloaddition of o-(Silylmethyl)benzyl Carbonates with Alkenes

Abstract

The palladium complex, which is generated in situ from Pd(η ³-C₃H₅)Cp and tris(4-methoxy-3,5-dimethylphenyl)phosphine, catalyzed the [4+2] cycloaddition of o-(silylmethyl)benzyl carbonates with alkenes. The reaction of the benzyl esters with methyl crotonate gave methyl 3-methyltetralin-2-carboxylate in 84% yield with 2% catalyst loading.

Key words

catalysis - cycloaddition - o-quinodimethanes - alkenes - palladacycles

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