A Cascade Sonogashira Cross-Coupling-Substitution-Elimination Reaction for the Synthesis of Linear Conjugated Dienynes.

The engagement in tandem of well-known organic reactions such as the Pd-catalyzed Sonogashira cross-coupling reaction, nucleophilic substitution and elimination reactions, enables the synthesis of otherwise difficult to obtain linear dienynes, in moderate to high yields. This retrosynthetic approach opens new ways to prepare highly conjugated alkenes and alkynes. Furthermore, ionic liquids are suitable solvents to perform the cascade reaction and recycle the metal catalysts.