NHC‐Stabilized Dialanes(4) of Al<sub>2</sub>Mes<sub>4</sub>
Luis Werner, Julika Hagn, Udo Radius
Abstract
Abstract The synthesis and characterization of novel N ‐heterocyclic carbene (NHC) stabilized dialanes Al 2 Mes 4 as well as first investigations concerning the reactivity of these compounds are reported. The synthesis of these compounds proceeds via the mesityl‐substituted alanes (NHC)⋅AlHMes 2 (NHC=IMe Me {=1,3,4,5‐tetramethyl‐imidazolin‐2‐ylidene}, I i Pr Me {=1,3‐di‐ iso ‐propyl‐4,5‐dimethylimidazolin‐2‐ylidene}) and iodo‐alanes (NHC)⋅AlIMes 2 (NHC=IMe Me , I i Pr Me ). Metallic reduction of (NHC)⋅AlIMes 2 afforded the new NHC‐stabilized dialanes (NHC) 2 ⋅Al 2 Mes 4 (NHC=IMe Me , I i Pr Me ). The NHC‐ligated dialanes are thermally robust and storable synthons for the dialane Al 2 Mes 4 . First reactivity studies on (IMe Me ) 2 ⋅Al 2 Mes 4 towards small molecules confirm this, as this compound shows controlled and selective reactions with several substrates. Reaction with CuCl leads to oxidation of the dialane and formation of (IMe Me )⋅AlClMes 2 , reactions with pyridine N ‐oxide and t Bu−N=C=S, respectively, gave the chalcogenide‐bridged dimers {(IMe Me )⋅AlMes 2 } 2 ‐ μ ‐E (E=O, S), and reaction with acetylene afforded the dimetallaacetylide {(IMe Me )⋅AlMes 2 } 2 ‐ μ ‐(C≡C).