A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 143

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 994
Function: getPubMedXML

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3134
Function: GetPubMedArticleOutput_2016

File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

Coplanar binuclear group 4 post-metallocene complexes supported by chelating μ-(σ-aryl) ligands: characterisation and olefin polymerisation catalysis. | LitMetric

Coplanar binuclear group 4 post-metallocene complexes supported by chelating μ-(σ-aryl) ligands: characterisation and olefin polymerisation catalysis.

Dalton Trans

Department of Chemistry and Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.

Published: December 2023

AI Article Synopsis

  • The report discusses the development of bimetallic catalyst systems based on the previously established M-[O,N,C] [pyridine-2-phenolate-6-(σ-aryl)] framework that allows for controlled metal-metal distances and enhanced cooperativity in reactions.
  • Binuclear complexes are produced selectively and characterized using multinuclear NMR spectroscopy, while comparison is made with mononuclear versions.
  • Bimetallic derivatives made from Ti, Zr, and Hf have been analyzed using X-ray crystallography, showing effective ethylene and ethylene/1-octene polymerization performance with the bimetallic Ti catalysts yielding better results than their mononuclear counterparts

Article Abstract

The report concerns expansion of the previously developed M-[O,N,C] [pyridine-2-phenolate-6-(σ-aryl)] catalyst system into rigid, coplanar bimetallic assemblies, which afford metal-metal distances that are predetermined yet amenable for cooperativity, as well as locked-in "" orientation of binding sites that offer the same direction of access for substrates. The binuclear complexes are generated in a regioselective manner to yield hydrogen atoms (not ) at the central μ-aryl moiety, and have been characterised by multinuclear NMR spectroscopy. The "" (showing opposite directions of access) and mononuclear analogues have also been prepared for comparison purposes. Six -type bimetallic derivatives of Ti, Zr and Hf have been characterised by X-ray crystallography, to reveal metal-metal separations of 6.3-6.7 Å. For ethylene and ethylene/1-octene polymerisation reactions in conjunction with trityl borate, the -Ti catalysts display superior efficiencies and produced polymers with higher values than for the and mono-Ti congeners, thus indicating the possibility of favourable enchainment interactions and cooperative reactivity.

Download full-text PDF

Source
http://dx.doi.org/10.1039/d3dt03641cDOI Listing

Publication Analysis

Top Keywords

coplanar binuclear
4
binuclear group
4
group post-metallocene
4
post-metallocene complexes
4
complexes supported
4
supported chelating
4
chelating μ-σ-aryl
4
μ-σ-aryl ligands
4
ligands characterisation
4
characterisation olefin
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!

A PHP Error was encountered

Severity: Notice

Message: fwrite(): Write of 34 bytes failed with errno=28 No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 272

Backtrace:

A PHP Error was encountered

Severity: Warning

Message: session_write_close(): Failed to write session data using user defined save handler. (session.save_path: /var/lib/php/sessions)

Filename: Unknown

Line Number: 0

Backtrace: