When Metathesis Reactions Go Wrong: Novel Structural Consequences

摘要

The complex [Yb(Ph(2)pz)(3)(LiOBu)](2) (1) (Ph(2)pz = 3,5-diphenylpyrazolate), fortuitously obtained from reaction of Yb metal with a lithium containing sample of [SnMe3(Ph(2)pz)] at elevated temperatures forms a centrosymmetric butoxy- and pyrazolate-bridged open box structure. Each ytterbium atom is eight coordinate with one chelating Ph(2)pz ligand, one mu-eta(2):eta(2) bridging pyrazolate, one mu-eta(2)(Yb):eta(4)(Li) Ph(2)pz group and two bridging butoxide ligands. Each lithium atom is unsymmetrically chelated by an eta(2-) Ph(2)pz group, eta(4)(N,C(pz)C-2(Ph)) bonded by another pyazolate group, and bridged through a butoxide oxygen atom to two ytterbium atoms. The type of eta(4)-pyrazolate coordination is unprecedented and is the first observation of interactions to a metal by the Ph rings of the Ph(2)PZ ligand. The complex [Li(dme)(3)]-[Eu(Ph(2)pz)(3)(dme)] (2) obtained from reaction of Eu metal with the same sample of [SnMe3(Ph(2)pz)] in dine at room temperature is a charged separated species with the first anionic pyrazolatolan-thanoidate(II) complex in which europium is eight coordinate with three chelating Ph(2)pz ligands and a chelating dine.