RT info:eu-repo/semantics/article
T1 Synthetic and reactivity studies of mono- and dicyclopentadienyl titanium, zirconium and hafnium complexes with the chlorodimethylsilyl-cyclopentadienyl ligand. X-ray molecular structure of Hf{(η5-C5H4)SiMe2OSiMe2(η5-C5H4)}Cl2 and Zr(η5-1,3-tBu2C5H3)(η5-C5H4SiMe2-η-NtBu)Cl
A1 Ciruelos Ortega, Santiago
A1 Sebastián Navas, Alfredo
A1 Cuenca Agreda, José Tomás
A1 Gómez Sal, Pilar
A1 Manzanero Castillo, Antonio
A1 Royo Gracia, Pascual
K1 Titanium
K1 Zirconium
K1 Hafnium
K1 Chlorodimethylsilyl-cyclopentadienyl
K1 Mixed dicyclopentadienyl
K1 Amido cyclopentadienyl
K1 Ciencia
K1 Química inorgánica
K1 Science
K1 Chemistry, inorganic
AB Reaction of the disilylated cyclopentadiene C5H4(SiClMe2)(SiMe3) with HfCl4, in heptane, gave the monocyclopentadienyl complex Hf(η5-C5H4SiClMe2)Cl3 (1c). Addition of two equivalents of C5H5(SiClMe2) to a solution of MCl4, in toluene under reflux and in the presence of two equivalents of NEt3, afforded the dichloro derivatives M(η5-C5H4SiClMe2)2Cl2 [M=Ti (2a), Hf (2c)]. Compounds 2a and 2c react with a stoichiometric amount of water with selective hydrolysis of the SiCl bonds to give the tetramethyldisiloxane-bridged diciclopentadienyl complexes M{(η5-C5H4)SiMe2OSiMe2(η5-C5H4)}Cl2 [M=Ti (3a), Hf (3c)]. The reaction of the trichloro metal compounds M(η5-C5H4SiClMe2)Cl3 with Tl(1,3-tBu2C5H3), K(C5Me5) or Tl(C5H5) afforded the dichloro mixed dicyclopentadienyl MCp′(η5-C5H4SiClMe2)Cl2 derivatives [Cp′=1,3-tBu2C5H3, M=Ti (4a), Zr (4b), Hf (4c); Cp′=C5Me5, M=Zr (5b), Hf (5c); Cp′=C5H5, M=Hf (6c)]. The SiCl bond of the mixed dicyclopentadienyl complexes M(η5-1,3-tBu2C5H3)(η5-C5H4SiClMe2)Cl2, [M=Ti (4a), Zr (4b), Hf (4c)] reacts selectively with one equivalent of LiNHtBu in toluene at 50–60°C to give the amidosilyl(cyclopentadienyl) compounds M(η5-1,3-tBu2C5H3)(η5-C5H4SiMe2NHtBu)Cl2, [M=Ti (7a), Zr (7b), Hf (7c)]. The same reaction with two equivalents of the lithium amide gives the ansa-cyclopentadienylsilyl-amido compounds M(η5-1,3-tBu2C5H3)(η5-C5H4SiMe2-η-NtBu)Cl [M=Ti (8a), Zr (8b), Hf (8c)]. The X-ray molecular structure of Hf{(η5-C5H4)SiMe2OSiMe2(η5-C5H4)}Cl2 (3c) and Zr(η5-1,3-tBu2C5H3)(η5-C5H4SiMe2-η-NtBu)Cl (8b) have been determined by diffraction methods.
PB Elsevier
SN 0022-328X
YR 2000
FD 2000
LK http://hdl.handle.net/10017/4208
UL http://hdl.handle.net/10017/4208
LA eng
NO Financial support for this research by DGICYT (Project PB97-0776) is gratefully acknowledged.
DS MINDS@UW
RD 25-abr-2024