Platinum(II)-catalyzed reaction of 2-alkynylbenzoates or benzothioates with vinyl ethers: A concise method for synthesis of 1-acyl-4-alkoxy- or 1-acyl-4-alkylsuifanylnaphthalene derivatives

A concise method for the preparation of 1-acyl-4-alkoxy- or 1-acyl-4-alkylsulfanyl naphthalenes has been developed by the reaction of o-ethynylbenzoates or benzothioates with vinyl ethers, in the presence of a catalytic amount of PtCl2. It is proposed that the reaction proceeds through [3 + 2]-cycloaddition of the platinum-containing carbonyl ylides followed by 1,2-alkyl migration.