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Hidden Boron Catalysis: A Cautionary Tale on TMEDA Inhibition
Julie Macleod1, Andrew D Bage1, Leonie M Meyer1
1EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom.
Abstract:
Hidden boron catalysis plagues catalyzed hydroboration reactions, with the "catalyst" acting to mediate the decomposition of HBpin/HBcat to BH3 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.
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