Abstract
Hidden boron catalysis plagues catalyzed hydroboration reactions, with the "catalyst" acting to mediate the decomposition of HBpin/HBcat to BH(3) which is the actual (hidden) catalyst. N,N,N',N'-Tetramethylethylenediamine (TMEDA) has been used to identify hidden boron catalysis through trapping/inhibition. Kinetic analyses showed that TMEDA inhibition is only applicable below 60 °C and that other amine traps are likewise ineffective. Awareness of this temperature limitation reveals widespread hidden catalysis in previous methods and should limit future false negative tests.