Efficient synthesis of styrene derivatives through ethenolysis of renewable propenylbenzenes

• Styrene derivatives are important flavor and locust pheromone. • The synthesis is made in one step from renewable 1-propenylbenzenes. • Commercial ruthenium metathesis catalysts were employed. • Unprecedented turnover numbers for this reaction were achieved. Functionalized styrenes were obtained by the ethenolysis of renewable 1-propenylbenzenes in a very efficient synthetic pathway. Some of the products are valuable food & flavor ingredients (4-vinylguaiacol) or locust pheromone (4-vinylanisole). The catalysts employed were ruthenium-alkylidene complexes bearing a N-heterocyclic carbene as a ligand, which bulkiness proved to be important for the catalysis output. The judicious choice the reaction conditions was critical to enable near quantitative yields under mild conditions in short reaction times. More strikingly, the catalyst load could be reduced to 0.01 mol%, keeping good conversion and selectivity.