A study on the reactivity of alumazene

                                         Iva Kollhammerová


            Alumazene is the only example of trimeric iminoalanes. Its structure consists of a six
membered ring, where three aluminium and three nitrogen atoms regularly alternate. This ring is
stabilized by a bulky organic substituent at each nitrogen atom and one methyl group at each
aluminium atom. It is an inorganic analogue of benzene or borazine. In the comparison of
aromaticity, borazine is less aromatic than benzene, alumazene exhibits no aromaticity in this
series.^1, 2

            In case of borazine, a Lewis acid molecule can be coordinated to the nitrogen atom in
the structure, or Lewis acid and Lewis base together can be coordinated to borazine. In contrast
alumazene coordinates only Lewis base molecules to the aluminium atoms. ^3, 4, 5

            One group of reactions is substitution of alumazene. The three methyl groups at
aluminium atoms are sequentially substituted with another atom or group. In our case we substituted
the methyl groups with halogens (Cl, Br). In this area four new compounds were prepared and their
crystal structures characterized. ^6, 7

            Another group of reactions is coordination reactions of Lewis bases. In this area two
new adducts with acetonitrile and deuteroacetonitrile were prepared, subsequently structurally
characterized and their stability was studied by tensimetric method and quantum-chemical
calculations.

            Reactions of alumazene with quinolones constitute the last group of reactions. This
type of reaction can be characterized as addition at a formal double bond Al-N in the ring. In this
type of reaction, the ring is destroyed and new structures are formed.


References:

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[2] Lisovenko, A. S., Timoshkin, A. Y., Russ. J. General Chem., 2011, 81, 831

[3] Löbl, J., Necas, M., Pinkas, J., Main Group Chemistry, 2006, 5, 79

[4] Löbl, J., Ph.D. Thesis, 2007

[5] Lisovenko A. S., Timoshkin A. Y., Inorganic Chemistry, 2010, 49, 10357

[6] Davydova, E.I., Sevastinova, T. N., Suvorov, A. V., Timoshkin, A. Y., Coordination Chemistry
Reviews, 2010,  254, 2031

[7] Doinikov, D. A., Kollhammerova, I., Löbl, J., Necas, M., Timoshkin, A. Y., Pinkas, J., J.
Organomet. Chem., 2016, 809, 38