Activation of Small Molecules: Can Boron act as a Transition Metal?
Institute for Inorganic Chemistry
Institute for Sustainable Chemistry & Catalysis with Boron
Julius-Maximilians-University of Würzburg
Würzburg, Germany
E-mail: holger.braunschweig@uni-wuerzburg.de
The activation of small molecules is generally associated with transition metals (TMs) and constitutes the basis of catalysis. It was earlier believed that TM catalysts are required to facilitate processes such as the activation of H2 and other unreactive substrates. However, exciting recent developments in main group element chemistry have shown that carbenes, FLPs and heavy main group species are capable of TM-like activation reactions.[1] Our ongoing studies on low-oxidation-state boron compounds such as borylenes, diborenes, and diborynes have shown that these low-valent species exhibit a very rich chemistry, which is distinctly different from that of common compounds derived from boron in the oxidation state +3. Particularly interesting is the metal-like behavior of some borylenes and diborynes,
which form CO complexes analogous to TMs, bind and convert H2 and unsaturated organic substrates under mild conditions, and even activate and reduce N2.[2]
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