Formation of bimetallic, trimetallic, and pentametallic yttrium methoxide and methoxide oxide complexes from reactions of alkali-metal methoxides with bis(cyclopentadienyl)yttrium chloride

• Published in: Inorganic chemistry 1992-06, Vol.31 (12), p.2492-2501
• Main Authors: Evans, William J, Sollberger, Mark S, Shreeve, Julie L, Olofson, Jeffrey M, Hain, John H, Ziller, Joseph W
• Format: Article
• Language: English
• Subjects: 400201 - Chemical & Physicochemical Properties; BOND ANGLE; BOND LENGTHS; CHEMICAL PREPARATION; CHEMICAL REACTION YIELD; Chemistry; COHERENT SCATTERING; COMPLEXES; Condensed matter: structure, mechanical and thermal properties; DIFFRACTION; DIMENSIONS; DIMERS; Exact sciences and technology; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; LENGTH; LIGANDS; MOLECULAR STRUCTURE; NMR SPECTRA; Organic chemistry; ORGANIC COMPOUNDS; ORGANOMETALLIC COMPOUNDS; Organometalloidal and organometallic compounds; Physics; Preparations and properties; SCATTERING; SPECTRA; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; SYNTHESIS; TRANSITION ELEMENT COMPLEXES; Transition metals derivatives; X-RAY DIFFRACTION; YIELDS; YTTRIUM COMPLEXES
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/ic00038a035

The superficially simple metathetical reaction of (C5H5)[sub 2]YCl(THF) [where C5H5=C[sub 5]H[sub 5]] with alkali-metal methoxides has been found to form a variety of products and product mixtures depending on reaction conditions. (C5H5)[sub 2]YCl(THF) reacts with NaOMe to form [(C5H5)[sub 2]Y([mu]-OMe)][sub 2] (1) in 80-95% yield depending on the method of isolation of the product. 1 can be generated analogously from KOMe in up to 75% yield depending on reaction conditions and the source of KOMe. The primary byproduct in KOMe reactions, which can be isolated in up to 20% yield, was identified as the trimetallic anion ([(C5H5)[sub 2]Y([mu]-OMe)][sub 2][(C5H5)[sub 2]Y]([mu][sub 3]-O))[sup [minus]] (2). The yield of 2 can be increased to as high as 70% by varying the reaction conditions and the (C5H5)[sub 2]YCl(THF) to KOMe stoichiometry. Me[sub 2]O has been isolated as a byproduct in this oxide-forming reaction. The previously characterized pentametallic complex (C5H5)[sub 5]Y[sub 5]([mu]-OMe)[sub 4]([mu][sub 3]-OMe)[sub 4]([mu][sub 5]-O) (3) is also formed in this reaction system. 3 can be obtained in high yield from the reaction of (C5H5)YCl[sub 2](THF)[sub 3], generated in situ, with 2 equiv of NaOMe in THF at reflux or from the reaction of (C5H5)[sub 2]YCl(THF) and MeOH-solvated KOMe. Crystallographic data have been obtained on 1-3 as well as the (trimethylsilyl)cyclopentadienyl analogue of 1 [(C[sub 5]H[sub 4]SiMe[sub 3])[sub 2]Y([mu]-OMe)][sub 2] (4) and its chloride precursor [(C[sub 5]H[sub 4]SiMe[sub 3])[sub 2]Y([mu]-Cl)][sub 2] (5). Complexes 1,4, and 5 are comprised of (C[sub 5]H[sub 4]R)[sub 2]Y (R = H, SiMe[sub 3]) bent metallocene units bridged by methoxide or chloride ligands.