The synthesis and characterization of novel N-heterocyclic carbene (NHC) stabilized dialanes Al2Mes4 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)·AlHMes2 (NHC = IMeMe3, IiPrMe4) and iodo-alanes (NHC)·AlIMes2 (NHC = IMeMe5, IiPrMe6). Metallic reduction of 5 and 6 afforded the new NHC-stabilized dialanes (NHC)2·Al2Mes4 (NHC = IMeMe7, IiPrMe8). The NHC-ligated dialanes are thermally robust and storable synthons for the dialane Al2Mes4. First reactivity studies on (IMeMe)2·Al2Mes47 towards small molecules confirm this, as 7 shows controlled and selective reactions with several substrates. Reaction with CuCl leads to oxidation of the dialane and formation of (IMeMe)·AlClMes210, reactions with pyridine N-oxide and tBu-N=C=S, respectively, gave the chalcogenide-bridged dimers ((IMeMe)·AlMes2)2-μ-E (E= O 11, S 12), and reaction with acetylene afforded the dimetallaacetylide ((IMeMe)·AlMes2)2-μ-(C≡C) 13.