Complexes of Four‐Membered Group 13 Metal(I) N‐Heterocyclic Carbene Analogues with Metal Carbonyl Fragments

The four‐membered gallium(I) and indium(I) heterocycles, [ : M(Giso)] (M = Ga or In; Giso = {[N(Ar)] 2 CN(C 6 H 11 ) 2 } – , Ar = C 6 H 3 i Pr 2 ‐2,6), were treated with a series of transition metal carbonyl complexes. These reactions afforded the complexes [Fe(CO) 4 {Ga(Giso)}], [(CO) 3 Co{μ‐Ga(Giso)} 2 Co(CO) 3 ], [Ru(CO) 2 (PPh 3 ) 2 {M(Giso)}] and [CpMo(CO) 2 {[(Giso)Ga] 2 OH}], which were crystallographically and/or spectroscopically characterized. The results of the study show that the two heterocycles can act as σ‐donor ligands, but they are not as nucleophilic as, for example, group 13 diyls, : MR (M = Ga or In; R = alkyl, aryl, etc.). In addition, the degree of π‐back‐bonding in their metal carbonyl complexes does not appear to be significant.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)