Abstract
The first carbocyclic gallylene [(ADC)(2)Ga(GaI(2))] and bis-gallylene [(ADC)Ga](2) (ADC = PhC{N(Dipp)C}(2); Dipp = 2,6-iPr(2)C(6)H(3)) featuring a central C(4)Ga(2) ring annulated between two 1,3-imidazole rings are prepared by KC(8) reductions of [(ADC)GaI(2)](2). Treatment of [(ADC)Ga](2) with Fe(2)(CO)(9) affords complex [(ADC)GaFe(CO)(4)](2) in which each Ga(i) atom serves as a two-electron donor. [(ADC)Ga](2) activates white phosphorus (P(4)) and the C(sp(2)) -F bond of aryl fluorides (ArF) to yield compounds [(ADC)Ga(P(4))](2) and cis-/trans-[(ADC)GaF(Ar)](2), respectively. [(ADC)Ga](2) undergoes oxidation with (Me(2)S)AuCl to give [(ADC)GaCl(2)](2), while with PhN[double bond, length as m-dash]NPh it forms [1 + 4]-cycloaddition product [(ADC)GaN(Ph)N[double bond, length as m-dash]C(6)H(5)](2) by the dearomatization of one of the phenyl rings.