Pyridine‐Stabilized Cationic Silanethione Tungsten Complexes: Synthesis, Structures, and Reactivity

Silanethione compounds, R2Si=S, have been recognized as highly reactive species. One reliable way to stabilize silanethione is its coordination to transition metal fragments to convert silanethione-coordinated transition metal complexes. Herein, we report the synthesis, structure, and reactivity of a second cationic silanethione tungsten complex [Cp*(OC)(3)W{S=SiR2(py)}]TFPB (R=Me (5 a), Ph (5 b), Cp*: eta(5)-C5Me5, py: pyridine, and TFPB-: [B{3,5-(CF3)(2)C6H3}(4)](-)). Complex 5 was obtained by H- abstraction from the Si atom in the corresponding silylsulfanyl complex Cp*(OC)(3)W(SSiR2H) (4) with Ph3CTFPB, followed by the addition of pyridine. The reaction of 5 with PhNCS and PMe3 produced [Cp*(OC)(3)W{SSiR2N(Ph)C(PMe3)(2)}]TFPB (R=Me (6 a), Ph (6 b)) via the elimination of pyridine and the addition of the 1,3-dipolar species PhNC(PMe3)(2) (A) to the Si atom.