A Genuine Stannylone with a Monoatomic Two‐Coordinate Tin(0) Atom Supported by a Bis(silylene) Ligand
Jian Xu, Chenshu Dai, Shenglai Yao, Jun Zhu, Matthias Drieß
Abstract
Abstract 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.