Reactions of Hydrazines with AlH3•NMe2Et - Formation of Aluminum-Nitrogen Heterocycles

Treatment of the alane-amine adduct AlH3 center dot NMe2Et with 1,2-diphenylhydrazine, H5C6-N(H)-N(H)-C6H5, afforded a five-membered Al2N3 heterocycle (1) by the elimination of hydrogen and partial cleavage of N-N bonds. The structure of I comprises two aluminum atoms bridged by a dianionic diphenylhydrazinediido (-H5C6-N-N-C6H5-) and an imido ligand (H5C6-N2-). Each aluminum atom is further attached to a terminal hydrogen atom and a (ethyl) dimethylamino group. 1-Aminopyrrole, H2N-NC4H4 gave a singular tricyclic cage compound (2) under similar conditions, The amino groups were completely deprotonated. N-N bond cleavage was not observed. Compound 2 possesses a central Al2N2 ring. Its nitrogen atoms are bridged by an Al2N group, whereas an N2Al group bridges both aluminum atoms. All nitrogen atoms are part of N-N bonds, and all metal atoms are further bonded to terminal hydrogen atoms. ((c) Wiley-VCH Verlag Gmbh & Co. KGaA, 69451 Weinheim, Germany, 2009)