Copper-Catalyzed Cross-Coupling Reactions of Bromoalkynols with Terminal Alkynes in Supercritical Carbon Dioxide

Abstract

Copper-catalyzed cross-coupling reactions of bromo­alkynols and terminal alkynes were carried out in supercritical carbon dioxide (scCO₂) to afford the corresponding unsymmetrical diynes with good yields. The reaction is sensitive to temperature and the pressure of CO₂. Methanol, as a cosolvent of scCO₂, could promote dissolution of the inorganic salt and thus facilitated the reaction. This new heterocoupling reaction system is more environmentally friendly than more traditional methods, since it uses scCO₂ as solvent and sodium acetate as base instead of amines.

Key words

unsymmetrical diynes - heterocoupling reaction - alkynes - supercritical carbon dioxide

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