Highly Active Iminopyridyl Iron-Based Catalysts for the Polymerization of Isoprene

Hashmi, Obaid-Hasan; Champouret, Yohan; Visseaux, Marc

Document type :

Article dans une revue scientifique: Article original

DOI :

10.3390/molecules24173024

Permalink :

http://hdl.handle.net/20.500.12210/13059

Title :

Highly Active Iminopyridyl Iron-Based Catalysts for the Polymerization of Isoprene

Author(s) :

Hashmi, Obaid-Hasan [Auteur]
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Champouret, Yohan [Auteur]

Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Visseaux, Marc [Auteur]

Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]

Journal title :

Molecules

Volume number :

Pages :

3024

Publication date :

2019-08

ISSN :

1420-3049

HAL domain(s) :

Chimie/Chimie de coordination

English abstract : [en]

A series of iminopyridyl-based ligands, 6-[(Ar)N=C(R)]-2-C6H5N [(Ar = 2,6-Me2-C6H3, R = Me (L1); Ar = 2,6-iPr2-C6H3, R = Me (L2); Ar = 2,6-Me2-C6H3, R = H (L3); Ar = 2,6-iPr2-C6H3, R = H (L4); Ar = 3,5-(CF3)2-C6H3, R = Me ...
Show more >A series of iminopyridyl-based ligands, 6-[(Ar)N=C(R)]-2-C6H5N [(Ar = 2,6-Me2-C6H3, R = Me (L1); Ar = 2,6-iPr2-C6H3, R = Me (L2); Ar = 2,6-Me2-C6H3, R = H (L3); Ar = 2,6-iPr2-C6H3, R = H (L4); Ar = 3,5-(CF3)2-C6H3, R = Me (L5); Ar = C6F5, R = Me (L6)], and their corresponding iron (II) complexes were developed to investigate their application in the controlled coordinative polymerization of isoprene. The modulation of steric and electronic properties within this family of ligands/pre-catalysts has shown to influence the stereo-selectivity and activity of the polymerization of isoprene after activation. Upon activation with various co-catalysts such as AliBu3/[Ph3C][B(C6F5)4], AlEt3/[Ph3C][B(C6F5)4] or MAO, the resulting catalysts produced polyisoprenes with an excellent conversion (>99% of 500–5000 equiv.) within less than 1 h (TOF > 500 h−1) and having a variety of stereo-/regio-regularities. The presence of electron-donating and withdrawing groups drastically impacted the activity and the stereoselectivity of the catalysts during the course of the polymerization of isoprene. When activated with AliBu3/[Ph3C][B(C6F5)4], the complexes {6-[(2,6-Me2-C6H3)N=C(Me)]-2-C6H5N}FeCl2 (C1) and {6-[(2,6-iPr2-C6H3)N=C(Me)]-2-C6H5N}FeCl2 (C2) exhibited moderate trans-1,4 selectivity (>67%) while the iron-based systems bearing related aldiminopyridyl ligands {6-[(2,6-Me2-C6H3)N=C(H)]-2-C6H5N}FeCl2 (C3) and {6-[(2,6-iPr2-C6H3)N=C(H)]-2-C6H5N}FeCl2 (C4) were found to afford significant cis-1,4 selectivity at low temperature (>86% at −40 °C). On the other hand, the ternary {6-[(3,5-(CF3)2-C6H3)N=C(Me)]-2-C6H5N}FeCl2 (C5) or {6-[(C6F5)N=C(Me)]-2-C6H5N}FeCl2 (C6)/AliBu3/[Ph3C][B(C6F5)4] catalytic combinations showed exceptional activity for the polymerization of isoprene (TOF > 1,000,000 h−1), albeit providing less stereoselectivity.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

ENSCL
CNRS
Centrale Lille
Univ. Artois
Université de Lille

Collections :

Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181

Research team(s) :

Méthodologie organométallique pour la catalyse homogène (MOCAH)

Submission date :

2019-09-25T15:12:32Z
2019-10-09T08:42:09Z
2023-01-18T11:39:55Z

Files

molecules-24-03024.pdf
Version éditeur
Open access
Access the document

Except where otherwise noted, this item's license is described as Attribution 3.0 United States

Version	Link	Modification date
3	20.500.12210/13059*	2023-01-18T11:35:15Z
2	20.500.12210/13059.2	2019-10-09T08:41:21Z
1	20.500.12210/13059.1	2019-09-25T15:12:32Z

Highly Active Iminopyridyl Iron-Based ...

BibTeX

CSV

Excel

RIS

Files

Version history

Highly Active Iminopyridyl Iron-Based ... BibTeX CSV Excel RIS

Files

Version history

Highly Active Iminopyridyl Iron-Based ...

BibTeX

CSV

Excel

RIS