Heavier group 13 metal(I) heterocycles stabilized by sterically demanding diiminophosphinates:a structurally characterized monomer-dimer pair for gallium

摘要

We have synthesized and characterized the monomeric diiminophosphinate-stabilized group 13 metal(I) complexes [LE:], L = PhP(NDip), Dip = 2,6-iPrCH; E = Ga (), In () and Tl (). In addition, we structurally characterized the dimeric complex [(LGa)], . Similar synthetic attempts using L = PhP(NMes), Mes = 2,4,6-MeCH afforded product mixtures from which the mixed oxidation state species [(L)GaI] was isolated. [LGa:] is converted with dry air to the gallium(III) oxide species [(LGaO)] . Density Functional Theory studies on [LE:] and [(LE)], E = Al-Tl, shed light on the bonding in these compounds and show that the newly formed E-E bonding interactions can be described as weak single σ-bond with no significant π-bonding contribution for E = Al, Ga. A large contribution to the dimer binding enthalpies results from London dispersion forces.