Kershaw Cook, LJ, Fisher, J, Harding, LP et al. (1 more author) (2015) An iron(ii) spin-crossover metallacycle from a back-to-back bis-[dipyrazolylpyridine]. Dalton Transactions. ISSN 1477-9226
Abstract
The syntheses of 4-mercapto-2,6-di(pyrazol-1-yl)pyridine (bppSH) and bis[2,6-di(pyrazol-1-yl)pyrid-4-yl]disulfide (bppSSbpp) are reported. In contrast to previously published "back-to-back" bis-[2,6-di(pyrazol-1-yl)pyridine] derivatives, which form coordination polymers with transition ions that are usually insoluble, bppSSbpp yields soluble oligomeric complexes with iron(ii) and zinc(ii). Mass spectrometry and DOSY data show that [{Fe(μ-bppSSbpp)}n](2n+) and [{Zn(μ-bppSSbpp)}n](2n+) form tetranuclear metallacycles in nitromethane solution (n = 4), although (1)H NMR and conductivity measurements imply the iron compound may undergo more fragmentation than its zinc congener. Both [{Fe(bppSH)2](2+) and [{Fe(μ-bppSSbpp)}n](2n+) exhibit thermal spin-crossover in CD3NO2 solution, with midpoint temperatures near 245 K. The similarity of these equilibria implies there is little cooperativity between the iron centres in the metallacyclic structures.
Metadata
Authors/Creators: |
|
---|---|
Copyright, Publisher and Additional Information: | (c) 2015, The Royal Society of Chemistry. This is an author produced version of a paper published in Dalton Transactions. Uploaded in accordance with the publisher's self-archiving policy |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemistry (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 05 May 2015 12:41 |
Last Modified: | 01 May 2016 06:26 |
Published Version: | http://dx.doi.org/10.1039/c5dt00732a |
Status: | Published |
Publisher: | Royal Society of Chemistry |
Identification Number: | https://doi.org/10.1039/c5dt00732a |
Related URLs: |