Rapid and Mild Synthesis of an NHC-Coordinated Bis(trimethylsilyl)silylene via Elimination of Halotrimethylsilane

Base-coordinated
silylenes are often used as electron-donating
ligands for metal complexes and low-coordinate species of main group
elements. However, the synthesis routes to base-coordinated silylenes
remain limited. Herein, we report a rapid and mild reaction providing
NHC-coordinated bis­(trimethylsilyl)­silylene 2, which
includes the coordination of 1,3,4,5-tetramethylimidazol-2-ylidene
(IMe4) to (Me3Si)3SiX (1, X= Cl, Br, and I) and the subsequent elimination of the corresponding
Me3SiX assisted by another IMe4 molecule. Silylene 2 undergoes not only the coordination to BPh3 and
the addition reactions with 2,3-dimethyl­butadiene and Me3SiI but also an unprecedented substitution reaction with (Me3Si)3SiI affording (Me3Si)3Si-substituted IMe4-coordinated silylene 6.