PALLADIUM(0)-CATALYZED CARBOXYLATIVE CYCLIZED COUPLING OF PROPARGYLIC ALCOHOL WITH ARYL HALIDES

In recent years considerable efforts have been made to use carbon dioxide (CO2) as a starting material in synthetic organic chemistry. However, the chemical utilization has thus far been rather limited. In the previous paper the authors reported that α-ethynyl tertiary alcohols such as 2-methyl-3-butyn-2-ol underwent cycloaddition with CO2 yielding α-methylene cyclic carbonates in good yield in the presence of cobaltocene, Ru or Cu catalysts. In this paper another example of the reaction of CO2 with sodium 2-methyl-3-butyn-2-olate (1) and aryl halides catalyzed by a palladium (0) complex to give cyclic vinylidene carbonates 2 is described.