Catalytic Reaction Tools for Selective Bromination: Carbon-Based Molecular Design

Bromine is an abundant elemental resource, and it has unique atomic properties leading to molecular functions and chemical techniques in and beyond synthetic organic chemistry. To exploit the high potential of bromine, catalytic methodologies are necessary for controlling the selectivity of bromination. However, conventional bromination tools are tolerated to a limited part of synthetic reactions due to the high reactivity, and the poor biocompatibility has disturbed the application to life science research. We developed bromination catalysts featuring a strained carbon-carbon double bond as the catalytic site, together with a brominating reagent bearing a carbon-bromine bond and a π-conjugated system, for applications in chemical biology via biocompatible catalytic bromination. We also found the utility of the strained olefin as a bromine scavenger, offering an alternative strategy for optimizing catalyst-controlled selectivity during bromination for organic synthesis. These reaction tools were designed using active sites bearing carbon platforms, which have high affinity with bromine and allow flexible molecular design, for controlling kinetics of bromination.