Halide ions as a highly efficient promoter in the Ru-catalyzed hydroesterification of alkenes and alkynes

Abstract

The presence of catalytic amounts of halide salts was found to enhance dramatically the reaction efficiency in the Ru-catalyzed hydroesterification of alkenes and alkynes using a chelating 2-pyridylmethyl formate by lowering the reaction temperature. On the basis of IR and NMR studies, the halide effect on the reaction is mainly attributed to the facile dissociation of the trirutheniumcarbonyl precursor into the presumed active metal species. With this milder condition, the substrate scope has been significantly broadened.