Half-Sandwich Tungsten Complexes With Silyl-Functionalized Eta(5)-Cyclopentadienyl Ligand

Treatment of tungsten-silanes Cp(L)(OC)(2)WSiMe2H [L = CO (1a), PMe3 (1b)] with nBuLi or LiN(iPr)(2), respectively, induces a silyl shift to the cyclopentadienyl ring, resulting in the formation of the tungsten-centered anions {[HMe2Si(C5H4)](L)(OC)(2)W} Li [L = CO (2a), PMe3 (2b) l. 2a, b are transformed to the neutral complexes [HMe2Si(C5SH4)](L)(OC2) [L = CO, PMe3; R = H, Me, SiMe2H, SiMe3, (3, 4a-c) l by interaction with HOAc, MeI, Me2Si(H)Cl and Me3SiCl. The tetramethyl derivative [ClMe2Si(C5Me4)](OC)(3)WH (6) is synthesized by reaction of CIMe2SiC5Me4H (5) with (MeCN)(3)W(CO)(3). Hydrolysis of the chlorosilyl tungsten complexes [ClMe2Si(C5R4)](OC)(3)WR'[R = H, Me; R' = H, Cl(6 - 8)] leads to the novel tungsten complexes [HOMe2Si(C5R4)](OC3)WR'[R = H, Me; R' = H, Cl (9a-d)], characterized by a eta(5)-cyclopentadienyl-bonded silanol group. The molecular structure of the silanol 9d is presented.