A new expeditious synthesis of the core scaffold of salvianolic acid F trough a one-pot sequential Heck coupling catalyzed by palladium nanoparticles in ionic liquids

A new expeditious synthesis of tetramethyl salvianolic acid F is presented. Starting from the naturally occurring veratrole, the target molecule is easily obtained in a one-pot mode via a sequential double Heck coupling catalyzed by palladium nanoparticles dispersed in ionic liquids. The present method involves the chemoselective displacement of two different halogen atoms present on the veratrole ring and limits the need for tedious experimental procedures. A 66% of overall yield can be achieved, that represents, as far as we know, one of the best results present in the literature, until now. This protocol can also open the way for the synthesis of unnatural salvianolic-like compounds with potential bioactivity.