Step Dance on a Pentagon: Copper(I) and Copper(I) --- Tungsten(0) Triphospholyl Triphenylphosphane Complexes

Zenneck U, Heinemann FW (2004)


Publication Type: Journal article

Publication year: 2004

Journal

Book Volume: 23

Pages Range: 1689-1697

DOI: 10.1021/om030570i

Abstract

[(3,5-di-teri-butyl-1,2,4-triphospholyl)Cu(PPh 3)] (8) is, in contrast to the related dinieric complex [(3,5-di-teri-butyl-1,2,4- triphospholyl)Cu(PMe 3) 2] 2, monomeric and thighly fluxional in solution. 3 is synthesized from the corresponding trimethylstannyl 1,2,4-triphosphole la and [ClCu(PPh 3)] 4. Evidence for a three-sided rearrangement process between different molecular structures in solution could be obtained from dynamic 31P NMR spectroscopy. An η 5-π coordination mode (3a) of the copper ion is preferred at room temperature. The equilibrium shifts to the two spectroscopically distinguishable, but almost isoenergetic, σ complexes 3b and 3c at low temperature, which interconvert with the activation barrier ΔG‡ = 37 kJ/mol. The σ-donor orbitals of the triphospholyl ligand are believed to be an sp 3 hybrid P orbital in the case of 3b and an sp 2 P lone pair for 3c. The reaction of 3 with [(THF)W(CO) 5] leads to the binuclear CuW complex 4 and the trinuclear W 2Cu complex 5 with σ-phosphorus-coordinated W(CO) 5 moieties. 5 bears an additional η 5-π coordinated W(CO) 3 unit and a unique W-Cu-P bridge, as established by X-ray crystallography. Both complexes are fluxional in solution, and the activation barriers of their rearrangement processes have been established.

Authors with CRIS profile

How to cite

APA:

Zenneck, U., & Heinemann, F.W. (2004). Step Dance on a Pentagon: Copper(I) and Copper(I) --- Tungsten(0) Triphospholyl Triphenylphosphane Complexes. Organometallics, 23, 1689-1697. https://dx.doi.org/10.1021/om030570i

MLA:

Zenneck, Ulrich, and Frank Wilhelm Heinemann. "Step Dance on a Pentagon: Copper(I) and Copper(I) --- Tungsten(0) Triphospholyl Triphenylphosphane Complexes." Organometallics 23 (2004): 1689-1697.

BibTeX: Download