Nickel Complexes Featuring Iminophosphorane–Phenoxide Ligands for Catalytic Ethylene Dimerization

Thibault Cheisson (1) , Thi-Phuong-Anh Cao (1) , X. F Le Goff (1) , Audrey Auffrant (1)

1 LCM - Laboratoire de chimie moléculaire

A series of bidentate ligands associating an iminophosphorane and a phenoxide were synthesized and coordinated to nickel(II), leading initially to bimetallic KNi adducts. Replacement of the potassium by another metal allowed the isolation and characterization of bimetallic LiNi and AlNi complexes, while addition of one equivalent of triphenylphosphine gave access to monometallic complexes. The same type of complex was obtained with the coordination of a tridentate ligand incorporating a supplementary amine donor. These paramagnetic complexes were characterized by elemental analysis, and some of them by X-ray diffraction, evidencing a tetrahedral nickel center. They were shown to efficiently catalyze the oligomerization of ethylene in the presence of Et2AlCl (Al/Ni = 22.5) with TOF up to 72  000 mol(C2H4)/mol(Ni)/h, giving selectively butene (more than 97%) with at best 93% of 1-C4.

Domaines: Chimie de coordination; Catalyse; Chimie organique

Thibault Cheisson, Thi-Phuong-Anh Cao, X. F Le Goff, Audrey Auffrant. Nickel Complexes Featuring Iminophosphorane–Phenoxide Ligands for Catalytic Ethylene Dimerization. Organometallics, 2014, 33 (21), pp.6193-6199. ⟨10.1021/om500880g⟩. ⟨hal-02003812⟩