THE SPECTROSCOPIC PROPERTIES AND X-RAY CRYSTAL-STRUCTURE OF A DISCRETE MOLECULAR ALANE, DIMETHYLAMIDOALANE, [ME2NALH2]3

The vibrational, H-1 and C-13 NMR, and mass spectra of dimethylamidoalane (1) have been determined and analysed. The implications of these and other results have been confirmed by the X-ray crystal structure determination of 1, which reveals a discrete molecular species, [Me2NAlH2]3, containing a six-membered [AlN]3 ring in a chair conformation complying with C(3-upsilon) symmetry (1876 reflections). The mean values for salient interatomic distances and angles are: r(Al-N) 1.936(3), r(C-N) 1.505(5), r(Al-H) 1.55 angstrom, angles N-Al-N 108.8(1), angles Al-N-Al 114.9(1) and angles C-N-C 106.2(3)-degrees. The properties of the alane are compared with those of related compounds.