Copper(I)-Catalyzed Formation of Isoquinoline and QuinolineSubstituted Isobenzofurans

An efficient synthetic organic transformation was developed toaccess isoquinoline-substituted isobenzofurans by reaction of substituted 1,5-diynes with isoquinolineN-oxides. Moderate to excellent yields of isoquinoline-derived isobenzofurans were achieved by formation of a new C-C and two C-O bonds in the presence of copper catalyst in one pot. whereas quinoline-substituted isobenzofurans were obtained when the reaction was conductedusing quinolineN-oxides and 1,5-diynes in the presence copper catalyst.

Automated summary

An efficient synthetic method was developed for accessing isoquinoline-substituted isobenzofurans. By reacting substituted 1,5-diynes with isoquinoline N-oxides in the presence of a copper catalyst, moderate to excellent yields of isoquinoline-derived isobenzofurans were achieved. The reaction also yielded quinoline-substituted isobenzofurans when quinoline N-oxides and 1,5-diynes were used instead.