Issue 106, 2016, Issue in Progress

A novel class of nickel(ii) complexes containing selenium-based bidentate ligands applied in ethylene oligomerization

Abstract

A series of nickel(II) complexes [NiBr2(N^Se)2] (Ni1–Ni5) based on bidentate N^Se ligands were prepared by reacting arylselenyl–pyrazolyl ligands (L1–L5) with NiBr2(DME) (DME = 1,2-dimethoxyethane). All Ni complexes were characterized by IR spectroscopy, elemental analysis, high-resolution mass spectrometry (HRMS), and by X-ray crystallography for Ni4. X-ray crystallographic analyses of Ni4 revealed an octahedral environment for the nickel atom and the presence of selenium–nickel bonds. Upon activation with methylaluminoxane (MAO), all Ni complexes showed moderate to good activities in ethylene oligomerization [TOF = 6.2–23.0 × 103 (mol ethylene) per (mol Ni) per h], producing mostly α-C4 (87.2–94.1 wt%) as the main product. The ligand environment, i.e. the substituents on the pyrazolyl and arylselenyl units, as well as the reaction parameters, influence the catalytic activity and selectivity towards the production of 1-butene. Under optimized reaction conditions (toluene, 400 equiv. of MAO, 40 °C and 20 min), the Ni2/MAO catalytic system yielded TOF values up to 109.2 × 103 (mol ethylene) per (mol Ni) per h with good selectivities for α-C4 (85.4 wt%).

Graphical abstract: A novel class of nickel(ii) complexes containing selenium-based bidentate ligands applied in ethylene oligomerization

Supplementary files

Article information

Article type
Paper
Submitted
26 Jul 2016
Accepted
26 Oct 2016
First published
27 Oct 2016

RSC Adv., 2016,6, 104338-104344

A novel class of nickel(II) complexes containing selenium-based bidentate ligands applied in ethylene oligomerization

L. C. Dresch, B. B. de Araújo, O. D. L. Casagrande and R. Stieler, RSC Adv., 2016, 6, 104338 DOI: 10.1039/C6RA18987C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements