Synthesis of tetrasubstituted furans through a Cu/base-mediated cascade reaction from terminal alkynes and 1,2-diketones.

The expeditious construction of tetrasubstituted furans Cu/base-promoted cascade reactions of terminal alkynes with 1,2-diketones is described. This reaction proceeds smoothly, involving the formation of multiple chemical bonds tolerating a wide range of functional groups. The mechanism underlying these transformations has been thoroughly investigated, suggesting that 1,3-diyne serves as a key intermediate generated through oxidative coupling facilitated by the Cu catalyst.