Bis‐NHC Aluminium and Gallium Dihydride Cations [(NHC)<sub>2</sub>EH<sub>2</sub>]<sup>+</sup> (E = Al, Ga)
Andreas Hock, Luis Werner, Melanie Riethmann, Udo Radius
Abstract
The NHC alane and gallane adducts (NHC) · AlH 2 I (NHC = Me 2 Im Me 7 , i Pr 2 Im 8 , i Pr 2 Im Me 9 ) and (NHC) · GaH 2 I (NHC = Me 2 Im Me 10 , i Pr 2 Im Me 11 , Dipp 2 Im 12 ; R 2 Im = 1,3‐di‐organyl‐imidazolin‐2‐ylidene; Dipp = 2,6‐diisopropylphenyl; i Pr = isopropyl; Me 2 Im Me = 1,3,4,5‐tetra‐methyl‐imidazolin‐2‐ylidene) were prepared either by the simple yet efficient reaction of the NHC adduct (NHC) · AlH 3 with elemental iodine or by the treatment of (NHC) · GaH 3 with an excess of methyl iodide at room temperature. The reaction of one equivalent of the group 13 NHC complexes with an additional equivalent of the corresponding NHC afforded cationic aluminium and gallium hydrides [(NHC) 2 · AlH 2 ] + I− (NHC = Me 2 Im Me 13 , i Pr 2 Im 14 , i Pr 2 Im Me 15 ) and [(NHC) 2 · GaH 2 ] + I− (NHC = Me 2 Im Me 16 , i Pr 2 Im Me 17 ) and the normal and abnormal NHC coordinated compound [(Dipp 2 Im) · GaH 2 ( a Dipp 2 Im)]+I− 18 . Compounds 7 – 18 were isolated and characterized by means of elemental analysis, IR and multinuclear NMR spectroscopy and by X‐ray diffraction of the compounds 7 , 9 , 10 , 15 , 16 and 18 .