| Abstract: | A cyclic (R2SnAu)3 anion ( 3? , R2Sn=2,2,5,5‐tetrakis(trimethylsilyl)‐1‐stannacyclopentane‐1,1‐diyl) has been synthesized as a stable blue salt with K+(THF)6 through the reaction of stable dialkylstannylene 1 with R′3PAuCl (R′=Et, Ph) followed by the reduction with KC8. Crystallographic and NMR analysis shows that the six‐membered (SnAu)3 ring of 3? is planar and highly symmetric with an equal distance of six Au?Sn bonds. A UV/Vis spectrum of 3? in hexane reveals an intense absorption maximum at 598 nm. While cyclic Au3? with four valence electrons is known as unstable anti‐aromatic anion, 3? with three divalent tin ligands is stable σ aromatic anion with an unprecedented Möbius orbital array as predicted by the perturbation MO and CCSD analysis of 3? . |
