A Dimeric NHC–Silicon Monotelluride: Synthesis, Isomerization, and Reactivity

Abstract

The reaction of the NHC-disilicon(0) complex [(I Ar )Si=Si(I Ar )] (1,I Ar = DC{N(Ar)C(H)} 2 ,A r= 2,6-iPr 2 C 6 H 3 ) with two equiv of elemental Te in toluene at room temperature for three days afforded am ixture of the first dimeric NHCsilicon monotelluride [(I Ar )Si = Te] 2 (2)a nd its isomeric complex [(I Ar )Si(m-Te)Si(I Ar ) = Te](3). When the same reaction was performed for ten days,o nly 3 was isolated from the reaction mixture.Compound 1 reacted with four equiv of elemental Te in toluene for four weeks,w hich proceeded through the formation of 2, 3 and the NHC-disilicon tritelluride complex [{(I Ar )Si(=Te)} 2 Te]( 5-Te), to form the dimeric NHC-silicon ditelluride [(I Ar )Si( = Te)(m-Te)] 2 (4). The reactions are in line with theoretical mechanistic studies for the formation of 4.Compound 3 reacted with one equiv of elemental sulfur in toluene to form the first NHC-disilicon sulfur ditelluride complex [{(I Ar )Si(=Te)} 2 S] (5-S).