Distannabarrelenes with Three Coordinated SnII Atoms.

Abstract

Crystalline 1,4‐distannabarrelene compounds [(ADCAr)3Sn2]SnCl3 (3‐Ar) (ADCAr={ArC(NDipp)2CC}; Dipp=2,6‐iPr2C6H3, Ar=Ph or DMP; DMP=4‐Me2NC6H4) derived from anionic dicarbenes Li(ADCAr) (2‐Ar) (Ar=Ph or DMP) have been reported. The cationic moiety of 3‐Ar features a barrelene framework with three coordinated SnII atoms at the 1,4‐positions, whereas the anionic unit SnCl3 is formally derived from SnCl2 and chloride ion. The all carbon substituted bis‐stannylenes 3‐Ar have been characterized by NMR spectroscopy and X‐ray diffraction. DFT calculations reveal that the HOMO of 3‐Ph (ϵ=−6.40 eV) is mainly the lone‐pair orbital at the SnII atoms of the barrelene unit. 3‐Ar readily react with sulfur and selenium to afford the mixed‐valence SnII/SnIV compounds [(ADCAr)3SnSn(E)](SnCl6)0.5 (E=S 4‐Ar, Ar=Ph or DMP; E=Se 5‐Ph).