Back to Table of Contents

44049-AC3
All-Inorganic Metallocenes and Related Transition Metal Derivatives of the Heavier Group 15 Elements

John E. Ellis, University of Minnesota

Reaction of a quite labile polycyclic aromatic hydrocarbon or polyarene stabilized source of atomic Ti^2- with white phosphorus provided a high yield route to the only known example of an “all-inorganic” metallocene, decaphosphatitanocene dianion, [Ti(η⁵-P₅)₂]^2-, 1.¹ Although ³¹P NMR spectra suggest that related species exist for other transition metals, especially zirconium, none have been isolated and characterized to date. However, progress has been made in a key related area involving the synthesis and characterization of homoleptic polyarenemetalates. Because these compounds can serve as storable sources of atomic metal anions, they promise to be important reagents in the synthesis of new “all-inorganic” metallocenes and related species. Since the first report of a well-defined complex of this type, tris(η⁴-naphthalene)zirconate(2-),² only a few related compounds have been reported and remain unknown for most d-block elements. Recently, we reported on the first naphthalenecobaltate complex (see TOC), which is a remarkably reactive synthon for Co^1-.³ The first homoleptic polyarene iron complex has been obtained in the form of bis(η⁴-anthracene)ferrate(1-), also a rare example of a 17-electron complex containing a metal in a formal negative oxidation state (see Nugget).⁴ Related research involving previously funded PRF projects have been published on new homoleptic isocyanidemetalates, [Nb(CNXyl)₆]^-, Xyl = 2,6-dimethylphenyl,⁵ [Fe(CNXyl)₄]^2-,⁶ the first isolable dianion of this class, and [Ti(CO)₄(S₂CNR₂)]^-,⁷ unprecedented Ti(0) complexes containing Ti-S bonds. Finally, a retrospective article involving much prior research supported by the ACS-PRF, which provided the basis for the 2004 American Chemical Society F. Albert Cotton Award in Inorganic Synthesis, was published last year.⁸

(1) Urnezius, E.; Brennessel, W. W.; Cramer, C. J.; Ellis, J. E.; Schleyer, R. v. R. Science, 2002, 95, 832; (2) Jang, M.; Ellis, J. E. Angew. Chem. Int. Ed. 1994, 33, 1973; (3) Brennessel, W. W.; Young, V. G.; Ellis, J. E. Angew. Chem. Int. Ed. 2006, 45, 7268; (4) Brennessel, W. W.; Jilek, R. E.; Ellis, J. E. Angew. Chem. Int. Ed. 2007, 46, 6132; (5) Barybin, M. V.; Brennessel, W. W.; Kucera, B. E.; Minyaev, M. E.; Sussman, V. J.; Young, V. G.; Ellis, J. E.; J. Am. Chem. Soc. 2007, 129, 1141; (6) Brennessel, W. W.; Ellis, J. E.; Angew. Chem. Int. Ed. 2007, 46, 598; (7) Jilek, R. E.; Tripepi, G.; Urnezius, E.; Brennessel, W. W.; Young, V. G.; Ellis, J. E. Chem. Commun. 2007, 2639; (8) Ellis, J. E. Inorg. Chem. 2006, 45, 3167.

Back to top