A Genuine Stannylone with a Monoatomic Two‐Coordinate Tin(0) Atom Supported by a Bis(silylene) Ligand

The monoatomic zero‐valent tin complex (stannylone) {[Si(II)(Xant)Si(II)]Sn(0)} 5 stabilized by a bis(silylene)xanthene ligand, [Si(II)(Xant)Si(II)=PhC(NtBu)(2)Si(Xant)Si(NtBu)(2)CPh], and its bis‐tetracarbonyliron complex {[Si(II)(Xant)Si(II)]Sn(0)[Fe(CO)(4)](2)} 4 are reported. The stannylone 5 bearing a two‐coordinate zero‐valent tin atom is synthesized by reduction of the precursor 4 with potassium graphite. Compound 4 results from the Sn(II) halide precursor {[Si(II)(Xant)Si(II)]Sn(II)Cl}Cl 2 or {[Si(II)(Xant)Si(II)]SnBr(2)} 3 through reductive salt‐metathesis reaction with K(2)Fe(CO)(4). According to density functional theory (DFT) calculations, the highest occupied molecular orbital (HOMO) and HOMO‐1 of 5 correspond to a π‐type lone pair with delocalization into both adjacent vacant orbitals of the Si(II) atoms and a σ‐type lone pair at the Sn(0) center, respectively, indicating genuine stannylone character.