Facile Access to the Functionalized N-Donor Stabilized Silylenes PhC(NtBu)₂SiX (X = PPh₂, NPh₂, NCy₂, NiPr₂, NMe₂, N(SiMe₃)₂, OtBu)

Reactions of silylenes with organic substrates generally lead to silicon­(IV) compounds. Ligand substitution at the silicon­(II) atom of silylene, without changing the formal +2 oxidation state, is very rare. We report herein a straightforward route to functionalized silylenes LSiX (L = PhC­(NtBu)₂ and X = PPh₂ (1), NPh₂ (2), NCy₂(3), NiPr₂ (4), NMe₂ (5), N­(SiMe₃)₂ (6), OtBu (7)). Silylenes 1–7 have been prepared in quantitative yield by a modified ligand exchange reaction of PhC­(NtBu)₂SiCl (LSiCl) with the corresponding lithium or potassium salts. Compounds 1–7 were characterized by spectroscopic and spectrometric techniques. Single-crystal X-ray structures of 1, 3, and 4 were determined.