Fig. 2
Molecular structure of 1a. Hydrogen atoms, except hydrides, omitted. Ellipsoids shown at the 20% probability level, except aryl substituents, which are shown as wire frame. Selected bond lengths (Å): Al(1)–Al(2) 2.6317(15), Al(1)–Al(3) 2.6340(17), Al(1)–Al(2)′ 2.6472(15), Al(1)–Al(3)′ 2.6907(18), Al(2)–Al(3) 2.701(2), Al(2)–Al(3)′ 2.8257(14), Al(3)–N(2) 1.950(3), Al(2)–N(1) 1.925(3), Al(1)–H(1) 1.52(3), Al(2)–H(2) 1.55(3), Al(3)–H(3) 1.57(3), Mg(1)–H(2) 1.96(3), Mg(1)–H(3)′ 1.98(3). Symmetry operation: −x + 2, −y + 1, −z
