You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Reversible Dihydrogen Activation by Reduced Aryl Boranes as Main‐Group Ambiphiles
Contributor:
von Grotthuss, Esther;
Diefenbach, Martin;
Bolte, Michael;
Lerner, Hans‐Wolfram;
Holthausen, Max C.;
Wagner, Matthias
imprint:
Wiley, 2016
Published in:Angewandte Chemie International Edition
Language:
English
DOI:
10.1002/anie.201608324
ISSN:
1433-7851;
1521-3773
Origination:
Footnote:
Description:
<jats:title>Abstract</jats:title><jats:p>A new approach to main‐group H<jats:sub>2</jats:sub> activation combining concepts of transition‐metal and frustrated Lewis pair chemistry is reported. Ambiphilic, metal‐like reactivity toward H<jats:sub>2</jats:sub> can be conferred to 9,10‐dihydro‐9,10‐diboraanthracene (DBA) acceptors by the injection of two electrons. The resulting [DBA]<jats:sup>2−</jats:sup> ions cleave the H−H bond with the formation of hydridoborates under moderate conditions (<jats:italic>T=</jats:italic>50–100 °C; <jats:italic>p</jats:italic><1 atm). Depending on the boron‐bonded substituents R, the addition is either reversible (R=C≡C<jats:italic>t</jats:italic>Bu) or irreversible (R=H). The reaction rate is strongly influenced by the nature and the coordination behavior of the countercation (Li<jats:sup>+</jats:sup> slower than K<jats:sup>+</jats:sup>). Quantum‐chemical calculations support the experimental observations and suggest a concerted, homolytic addition of H<jats:sub>2</jats:sub> across both boron atoms. As proven by the successful conversion of Me<jats:sub>3</jats:sub>SiCl into Me<jats:sub>3</jats:sub>SiH, the system Li<jats:sub>2</jats:sub>[DBA]/H<jats:sub>2</jats:sub> appears generally relevant for the hydrogenation of element–halide bonds.</jats:p>