(2-Diphenylphosphinoethyl)cyclopentadienyl Complexes of Zirconium (IV): Synthesis, Crystal Structure and Dynamic Behaviour in Solutions.

Dmitrii P. Krut'ko, Maxim V. Borzov, Eduard N. Veksler, Andrei V. Churakov, and Judith A.K. Howard

Polyhedron, v.17 (22), p. 3889-3901 (1998)

ABSTRACT. The novel [h5:h1-(2-diphenylphosphinoethyl)cyclopentadienyl]trichlorozirconium (IV) [3] has been prepared via (2-diphenylphosphinoethyl)(trimethylsilyl)cyclopentadiene [2]. The structures of an adduct of [3] with tetrahydrofuran (THF) 3b (two crystal modifications) and of an ionic complex derived from [3] and ZrCl4 - {[h5:h1-(C5H4CH2CH2PPh2)ZrCl]2(m-Cl)3}2[(ZrCl4)2(m-Cl)2] [4] have been determined by an X-ray analysis. The X-ray and NMR data prove the existence of a Zr-P intramolecular coordination in [3] both in solid state and in non-solvating media within a broad range of temperatures. In THF solution the flexible equilibrium between adducts of [3] with one [3b] and two [3c] molecules of THF has been observed by variable-temperature NMR spectroscopy. The synthetic route to the simplest unsymmetrically ligated zirconocene (h5-C5H4CH2CH2PPh2)(h5-C5H5)ZrCl2 [5] derived from [3] has also been elaborated.

Laboratory of Coordination Organometallic Compounds