A new approach to main‐group H
2 activation combining concepts of transition‐metal and frustrated Lewis pair chemistry is reported. Ambiphilic, metal‐like reactivity toward H
2 can be conferred to 9,10‐dihydro‐9,10‐diboraanthracene (DBA) acceptors by the injection of two electrons. The resulting [DBA]
2? ions cleave the H?H bond with the formation of hydridoborates under moderate conditions (
T=50–100 °C;
p<1 atm). Depending on the boron‐bonded substituents R, the addition is either reversible (R=C≡C
tBu) or irreversible (R=H). The reaction rate is strongly influenced by the nature and the coordination behavior of the countercation (Li
+ slower than K
+). Quantum‐chemical calculations support the experimental observations and suggest a concerted, homolytic addition of H
2 across both boron atoms. As proven by the successful conversion of Me
3SiCl into Me
3SiH, the system Li
2[DBA]/H
2 appears generally relevant for the hydrogenation of element–halide bonds.
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