1,2‐Bis‐triphenylphosphoranylidenamino‐äthan als zweizähniger Ligand in Übergangsmetallkomplexen

Abstract

Die Umsetzungen von Ph3PNC2H4NPPh3 mit Übergangsmetallhalogeniden MX2 führen gemäß Gl. (1) zu neuartigen Bisiminophosphoran‐Komplexen des Typs M(Ph3PNC2H4NPPh3)X2 (M  Co, X  Cl 1 a, Br 1 b, J 1 c, M  Ni, X  Cl 2 a, Br 2 b, J 2 c; M  Hg, X  Cl 3, M  Cd, X  Cl 4). Es wird über Darstellung, Eigenschaften, magnetische Momente sowie Struktur der neuen Komplexe berichtet.

NiCl2(1,2-Diiminophosphorane) complexes: a new family of readily accessible and tuneable catalysts for oligomerisation of ethylene

“…The blue-violet complex 5 (Scheme 2) has already been prepared by reacting the 1,2-diiminophosphorane 1 with NiCl 2 in refluxing CH 3 CN, followed by treatment at 120 C under vacuum. 8 As observed for related a-diimines, 2 NiCl 2 (1,2-dimethoxyethane) reacted at room temperature in CH 2 Cl 2 with diiminophosphoranes 1-4, affording the corresponding complexes 5-8 (Scheme 2). Derivatives 5-8 exhibit low solubility in common organic solvents and, after washing with diethyl ether, are obtained in almost quantitative yield and high purity.…”

“…3c,d,4 As expected, the conformation of the two five-membered metallacycles is very different. The fivemembered metallacycle of complex 5, which contains sp 3hybridised C atoms, adopts a half-chair conformation [Ni(1)-N(1)-C(1)-C(2), 34.5 (8); Ni(1)-N(2)-C(2)-C(1), 35.6 (6)] with the two phosphino groups in a mutually trans configuration (Fig. 1).…”

“…It is very interesting to note that these data are very similar to those recorded for monomeric (a-diimine)-NiX 2 complexes. For example, (N,N 0 -di-tert-butylethylenediamine)NiBr 2 , which adopts a distorted tetrahedral geometry with planar coordinated N atoms, exhibits Ni-N bond lengths of 1.996(7) and 2.002 (8) + A while the N-Ni-N angle reaches 82.5(3) . 10…”