Electrophilic AlIII species have long dominated the aluminum reactivity towards arenes. Recently, nucleophilic low‐valent AlI aluminyl anions have showcased oxidative additions towards arenes C−C and/or C−H bonds. Herein, we communicate compelling evidence of an AlII radical addition reaction to the benzene ring. The electron reduction of a ligand stabilized precursor with KC8 in benzene furnishes a double addition to the benzene ring instead of a C−H bond activation, producing the corresponding cyclohexa‐1,3(orl,4)‐dienes as Birch‐type reduction product. X‐ray crystallographic analysis, EPR spectroscopy, and DFT results suggest this reactivity proceeds through a stable AlII radical intermediate, whose stability is a consequence of a rigid scaffold in combination with strong steric protection.

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Partially or fully reduced transition metal oxides show extraordinary electronic and catalytic properties but are usually prepared by high temperature reduction reactions. This study reports the systematic investigation of the fast mechanochemical reduction of rutile‐type TiO2 and H‐Nb2O5 to their partially reduced black counterparts applying NaH and LiH as reducing agents. Milling time and oxide to reducing agent ratio show a large influence on the final amount of reduced metal ions in the materials. For both oxides LiH shows a higher reducing potential than NaH. An intercalation of Li+ into the structure of the oxides was proven by PXRD and subsequent Rietveld refinements as well as 6Li solid‐state NMR spectroscopy. The products showed a decreased band gap and the presence of unpaired electrons as observed by EPR spectroscopy, proving the successful reduction of Ti4+ and Nb5+. Furthermore, the developed material exhibits a significantly enhanced photocatalytic performance towards the degradation of methylene blue compared to the pristine oxides. The presented method is a general, time efficient and simple method to obtain reduced transition metal oxides.

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