Organyl oxoboranes (RBO) are valuable reagents in organic synthesis due to their role in Suzuki coupling reactions. However, organyl oxoboranes (RBO) are only found in trimeric forms (RBO3) commonly known as boronic acids or boroxins; obtaining their monomers has proved a complex endeavor. Here, we demonstrate an oligomerization-free formation of organyl oxoborane (RBO) monomers in the gas phase by a radical substitution reaction under single collision conditions in the gas phase. Using the cross molecular beams technique, phenyl oxoborane (C6H5BO) is formed through the reaction of boronyl radicals (BO) with benzene (C6H6). The reaction is indirect, initially forming of a van-der-Waals complex that isomerizes below the energy of the reactants, eventually forming phenyl oxoborane by hydrogen emission in an overall exoergic radical - hydrogen atom exchange mechanism.
Gas Phase Synthesis of Phenyl Oxoborane (C6H5BO) via the Reaction of Boron Monoxide with Benzene
BALUCANI, Nadia;
2013
Abstract
Organyl oxoboranes (RBO) are valuable reagents in organic synthesis due to their role in Suzuki coupling reactions. However, organyl oxoboranes (RBO) are only found in trimeric forms (RBO3) commonly known as boronic acids or boroxins; obtaining their monomers has proved a complex endeavor. Here, we demonstrate an oligomerization-free formation of organyl oxoborane (RBO) monomers in the gas phase by a radical substitution reaction under single collision conditions in the gas phase. Using the cross molecular beams technique, phenyl oxoborane (C6H5BO) is formed through the reaction of boronyl radicals (BO) with benzene (C6H6). The reaction is indirect, initially forming of a van-der-Waals complex that isomerizes below the energy of the reactants, eventually forming phenyl oxoborane by hydrogen emission in an overall exoergic radical - hydrogen atom exchange mechanism.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
