Addition of Zinc Homoenolates to Acetylenic Esters and Amides : A Formal [ 3 + 21 Cycloaddition
نویسندگان
چکیده
The copper-catalyzed conjugate addition-cycloacylation reaction of zinc homoenolatee with acetylenic esters or acetylenic amides is described. The zinc homoenolate is prepared from [ (ethoxycyclopropy1)oxyltrimethylsilane and zinc chloride in ether. Addition of an acetylenic amide or ester provides 2-carboxamidoor 2-carboalkoxy-3-alkylcyclopent-2-en-l-ones ingood to excellent yields. The reaction can be carried out in the presence of a variety of sensitive functional groups including epoxides, &unsaturated esters, acetals, silyl ethers, and furans.
منابع مشابه
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