New Molecular Aluminum Chloride Amides [Cl 2 AlNEt 2 ] 2 and [HClAlNEt 2 ] 2 and their Boranate Analogues [(BH 4 ) 2 AlNEt 2 ] 2 and [H(BH 4 )AlNEt 2 ] 2

New molecular aluminium chloride amides [Cl 2 AlNEt 2 ] 2 and [HClAlNEt 2 ] 2 were prepared by salt‐elimination reactions from lithium diethylamide and aluminium hydride dichloride diethyl‐etherate or aluminium chloride, respectively. With LiBH 4 in n‐hexane they form the new boranates [(BH 4 ) 2 AlNEt 2 ] 2 and [H(BH 4 )AlNEt 2 ] 2 . X‐ray single crystal structure analyses reveal dimeric molecules with non‐planar four‐membered Al 2 N 2 rings in the solid state ([Cl 2 AlNEt 2 ] 2 ( 1 ): Pnma , V = 1606.3(2) Å 3 , Z = 4; [HClAlNEt 2 ] 2 ( 2 ): Pnma , V = 1453.7(2) Å 3 , Z = 4; [(BH 4 ) 2 AlNEt 2 ] 2 ( 3 ): C 2/ c , V = 1810.8(2) Å 3 , Z = 4; [H(BH 4 )AlNEt 2 ] 2 ( 4 ): Pnma , V = 1540.8(3) Å 3 , Z = 4). Bond lengths and angles are in the usual range for such compounds and torsion angles within the Al 2 N 2 rings vary from 1° to 14°. The packings of the dimeric molecules in compounds 1 , 2 , and 4 resemble a distorted hexagonal closest packing. NMR spectra corroborate the molecular structures from the solid state. CVD experiments with [HClAlNEt 2 ] 2 ( 2 ) as a single‐source precursor yield thin aluminium layers. [H(BH 4 )AlNEt 2 ] 2 ( 4 ) is the first structurally characterized hydride tetrahydridoborate compound of aluminium.