Glen M. Fern

Oxide, Sulfide, Selenide, and Borane Derivatives of Indenylphosphines

We report the preparation, isolation and characterization of oxide, sulfide, selenide, and borane derivatives of a series of indenylphosphines. Some members of the series had already been prepared, and we have completed the series. We have prepared (indenyl)xPh3-xPO (x = 1–3) for the oxide series, (indenyl)xPh3-xPS (x = 3) for the sulfides, (indenyl)xPh3-xPSe (x = 1,2) for the selenides, and (indenyl)xPh3-xPBH3 (x = 1–3) for the boranes. Linear relationships of the 31P NMR chemical shift with the number of indenyl groups were observed. The compounds were also characterized by 1H and 13C NMR spectroscopy and mass spectrometry. The solid-state structure of diindenylphenylphosphine selenide was determined by X-ray crystallography and found to be isomorphous with diindenylphenylphosphine sulfide. The solid-state structure of triindenylphosphine sulfide was also determined by X-ray crystallography and the indenyl groups were confirmed to all be the inden-3-yl isomer. Additionally, pentacarbonyl(triindenylphosphine)molybdenum(0), 1,3-bis(diphenylphosphino)indene diborane, and rac-bis(1-(diphenylphosphino)indenyl)ironII) diborane were prepared, isolated, and characterized.

Synthesis of the sterically constrained ligand precursor cyclopentadienyl-2,6-diphenylbenzene and structure of [(2,6-Ph2–C6H3-η5-C5H4)Zr(NEt2)3]

Abstract A Pd-catalysed Stille coupling of 2,6-diphenyliodobenzene with tributylcyclopentadienyltin gave the sterically constrained ligand precursor cyclopentadienyl-2,6-diphenylbenzene (1). Treatment of this precursor with tetrakis(diethylamido)zirconium(IV) gave the three-legged piano-stool complex [(2,6-Ph2–C6H3-η5-C5H4)Zr(NEt2)3] (2). Complex 2 was characterised by 1H- and 13C{1H}-NMR spectroscopy as well as by X-ray crystallography which showed significant distortions of the three-legged piano-stool geometry as a result of steric interactions with the bulky aryl substituent.