The first 1,2,4-thiadisiletane ring compound: synthesis from an overcrowded silylene and carbon disulfide

Abstract

Treatment of an extremely hindered disilene, (Z)-R(mes)SiSi(mes)R (R = 2,4,6-tris[bis(trimethylsilyl)-methyl]phenyl, mes = mesityl) with carbon disulfide in THF at 60 °C gives a novel 1,2,4-thiadisiletane-3-thione derivative, the formation of which is most likely interpreted in terms of a stepwise 2:1 addition reaction of the thermally generated overcrowded silylene R(mes)Si: to CS₂ followed by a skeletal rearrangement of the resulting 3,3′-spirobi[1,2-thiasilirane] intermediate.