Organoamido‐ and Aryloxo‐lanthanoids, 14. Organometallic Compounds of the Lanthanoids, 106. Synthesis and Characterisation of Complexes of Lanthanoid Pyrazolates with 1,2‐Dimethoxyethane and the X‐Ray Structures of (1,2‐Dimethoxyethane‐O1:O2)(1,2‐dimethoxyethane‐O1)tris(3,5‐diphenylpyrazolato)erbium(III) and catena‐Poly[tris(3,5‐di‐tert‐butylpyrazolato)‐μ‐(1,2‐dimethoxyethane‐O1:O2)‐neodymium(III)]

The complexes [Ln(Ph2pz)3 (DME)2] and [Ln(tBu2pz)3 (DME)] (Ln = La, Nd, Er; Ph2pzH = 3,5‐diphenylpyrazole; tBu2pzH = 3,5‐di‐tert‐butylpyrazole; DME = 1,2‐dimethoxyethane) have been prepared by reaction of the lanthanoid metal with bis(pentafluorophenyl)mercury and the pyrazole in DME. The molecular structures of [Er(Ph2pz)3 (DME)2] (3) and [Nd(tBu2pz)3 (DME)]∞ (5) have been determined by X‐ray diffraction. Complex 3 has nine‐coordinate Er with three chelating Ph2pz ligands and one chelating and one η1‐bound DME. There is a trigonal prismatic arrangement of the oxygen donors and the centres of the N – N bonds. 5 was found to be a linear polymer with transoid DME ligands bridging Nd(tBu2pz)3 units in a novel manner. The centres of the N – N bonds (which are essentially coplanar with Nd), and the oxygen donor atoms adopt an arrangement intermediate between trigonal‐bipyramidal and square‐pyramidal [O – Nd – O 153.5(2)°].