Metal amides

Metal amides (systematic name metal azanides) are a class of coordination compounds composed of a metal center with amide ligands of the form NR2−. Amide ligands have two electron pairs available for bonding. In principle, they can be terminal or bridging. In these two examples, the dimethylamido ligands are both bridging and terminal: File:Tris(dimethylamino)aluminium dimer.png|[[Tris(dimethylamino)aluminium dimer]]cite journal | doi = 10.1002/zaac.19835040909 | title = Dimethylaminoalane, H3−nAl[N(CH3)2]n, n = 1, 2, 3 Kristallstrukturen und Molekülspektren | year = 1983 | last1 = Ouzounis | first1 = K. | last2 = Riffel | first2 = H. | last3 = Hess | first3 = H. | last4 = Kohler | first4 = U. | last5 = Weidlein | first5 = J. | journal = Zeitschrift für anorganische und allgemeine Chemie | volume = 504 | issue = 9 | pages = 67–76}} File:Tris(dimethylamino)gallium dimer.png|[[Tris(dimethylamino)gallium dimer]]{{Cite journal | doi = 10.1016/S0277-5387(00)80578-1 | title = Structural and spectroscopic characterization of the compounds [Al(NMe2)3]2, [Ga(NMe2)3]2, [(Me2N)2Al{μ-N(H)1-Ad}]2 (1-Ad = 1-adamantanyl) and [{Me(μ-NPh2)Al}2NPh(μ-C6H4)] | year = 1990 | last1 = Waggoner | first1 = K.M. | last2 = Olmstead | first2 = M.M. | last3 = Power | first3 = P.P. | journal = Polyhedron | volume = 9 | issue = 2–3 | pages = 257–263}} File:Ti(NMe2)4.png|[[Tetrakis(dimethylamino)titanium]] File:Ta(NMe2)5.png|[[Pentakis(dimethylamido)tantalum]] In practice, bulky amide ligands have a lesser tendency to bridge. Amide ligands may participate in metal-ligand π-bonding giving a complex with the metal center being co-planar with the nitrogen and substituents. Metal bis(trimethylsilyl)amides form a significant subcategory of metal amide compounds. These compounds tend to be discrete and soluble in organic solvents. lithium amidesodium amide and potassium amide Lithium amides are the most important amides, as they are readily prepared from n-butyllithium and the appropriate amine, and they are more stable and soluble than the other alkali metal analogs.