RT info:eu-repo/semantics/article T1 Dinuclear cationic zirconium complexes with the fulvalene ligand. Synthesis and reactivity A1 Cuenca Agreda, Tomás A1 Galakhov, Mikhail V. A1 Jiménez Pindado, Gerardo A1 Royo Cantabrana, Eva A1 Royo Gracia, Pascual A1 Bochmann, Manfred K1 Zirconium K1 Cyclopentadienyl derivatives K1 Cationic dinuclear derivatives K1 Ciencia K1 Química inorgánica K1 Science K1 Chemistry, inorganic AB The reaction of B(C6F5)3 with the tetramethyl zirconium fulvalene derivative [Zr(C5H5)(CH3)2]2(μ-η5:η5-C10H8) 1a in CH2Cl2 at −60°C gives the cationic compound [{Zr(C5H5)}2(μ-CH3)(μ-CH2)(μ-η5:η5-C10H8)]+[BMe(C6F5)3]−2a. A similar reaction using the 1,3-di(tert-butyl) cyclopentadienyl derivative [Zr(1,3-tBu2-C5H3)(CH3)2]2(μ-η5:η5-C10H8) 1b affords a mixture of compounds, none of them being isolable as pure substances. However, monitoring the reaction of B(C6F5)3 with 1b by variable temperature NMR spectroscopy, between −80°C and 25°C, permits the observation, at low temperature, of the intermediate dimethyl μ-methyl cationic species [{Zr(1,3-tBu2-C5H3)(CH3)}2(μ-CH3)(μ-η5-η5-C10H8)]+8b which decomposes with evolution of methane to give the μ-methylene, μ-methyl complex [{Zr(1,3-tBu2-C5H3)}2(μ-CH3)(μ-CH2)(μ-η5:η5-C10H8)]+[BMe(C6F5)3] 2b. In dichloromethane or chloroform complexes 2a and 2b undergo slow conversion to the μ-chloro, μ-methylene derivatives [{ZrCp′}2(μ-Cl)(μ-CH2)(η5:η5-C10H8)]+[BMe(C6F5)3]− (Cp′ = C5H53a, 1,3-tBu2-C5H33b) by a halide abstraction process. Prolonged exposure of 3b to chlorocarbons gives the dichloro μ-chloro compound [{Zr(1,3-tBu2-C5H3)Cl}2(μ-Cl)(μ-η5:η5-C10H8)]+[BMe(C6F5)3]−9b. The addition of an excess of donor ligands to a solution of 2a in dichloromethane-d2 at −60°C affords the cationic adducts [{Zr(C5H5)}2(CH3)L(μ-CH2)(μ-η5:η5-C10H8)]+[BMe(C6F5)3]− [L = PMe3 (4a), PMe2Ph (5a), PPh3 (6a), THF (7a)] obtained as a mixture of syn- and anti-isomers. The compound 5a can be isolated as an analytically pure sample when this reaction is carried out in CH2Cl2. PB Elsevier SN 0022-328X YR 1997 FD 1997 LK http://hdl.handle.net/10017/4422 UL http://hdl.handle.net/10017/4422 LA eng NO British Council DS MINDS@UW RD 29-mar-2024