Ru(II)-Catalyzed Hydrodefluorination of Monofluoroalkenes.

Despite significant advances in C-F bond functionalization, the selective hydrogenative defluorination of monofluoroalkenes remains a considerable challenge due to competing over-reduction issues. Here, we report a practical and selective protocol for the hydrodefluorination of monofluoroalkenes, employing an inexpensive ruthenium(II) catalyst with sodium formate as a safe and convenient hydrogen source. This method enables the selective cleavage of C(sp2)-F bonds while minimizing overhydrogenation byproducts, thus providing efficient access to the corresponding alkenes. The reaction demonstrates broad functional group tolerance and is scalable to gram quantities.