Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism
We report the synthesis and magnetic and photomagnetic behaviour of a novel valence tautomeric cobalt complex, [Co(3,5-dbbq)2(μ-bpym)] (1) (3,5-dbbq = 3,5-di-tert-butyl-1,2-benzoquinone and μ-bpym = 2,2'-bipyrimidine). The synthesis is performed by reacting Co2(CO)8 and μ-bpym in the presence o...
Main Authors: | , , , , , |
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Format: | Journal article |
Language: | English |
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Royal Society of Chemistry
2015
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_version_ | 1797067091770081280 |
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author | Slota, M Blankenhorn, M Heintze, E Vu, M Hübner, R Bogani, L |
author_facet | Slota, M Blankenhorn, M Heintze, E Vu, M Hübner, R Bogani, L |
author_sort | Slota, M |
collection | OXFORD |
description | We report the synthesis and magnetic and photomagnetic behaviour of a novel valence tautomeric cobalt complex, [Co(3,5-dbbq)2(μ-bpym)] (1) (3,5-dbbq = 3,5-di-tert-butyl-1,2-benzoquinone and μ-bpym = 2,2'-bipyrimidine). The synthesis is performed by reacting Co2(CO)8 and μ-bpym in the presence of the ligand 3,5-dbbq in a mixed solvent under inert atmosphere. The magnetic behavior clearly shows the presence of electron transfer from the catecholate ligand to the cobalt center, producing valence tautomers of [Co(II)(SQ)2] with a transition temperature (T1/2) of 215 K. Photomagnetic studies, performed via both SQUID magnetometry and X-band electron paramagnetic resonance, show the clear presence of photoinduced valence tautomerism, at temperatures considerably higher than previous systems. A metastable charge distribution is observed, strengthening previous investigations on the character of mixed valence ligands. Entropy-driven valence tautomeric interconversion is observed, and drives the transition to the most stable charge distribution. The complex has the ability to coordinate and can be used as a photoswitchable building block, with the photomagnetic characterisation evidencing a metastable state lifetime of the photo-induced valence tautomeric process of ca. 2.9 × 10(4) s below 20 K. The observed yields are higher than ones in similar systems, showing that tiny changes in the molecular structures may have a huge impact. |
first_indexed | 2024-03-06T21:51:21Z |
format | Journal article |
id | oxford-uuid:4b603d4c-9670-478e-b5ac-31cc231acd62 |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-06T21:51:21Z |
publishDate | 2015 |
publisher | Royal Society of Chemistry |
record_format | dspace |
spelling | oxford-uuid:4b603d4c-9670-478e-b5ac-31cc231acd622022-03-26T15:43:13ZPhotoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerismJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:4b603d4c-9670-478e-b5ac-31cc231acd62EnglishSymplectic Elements at OxfordRoyal Society of Chemistry2015Slota, MBlankenhorn, MHeintze, EVu, MHübner, RBogani, LWe report the synthesis and magnetic and photomagnetic behaviour of a novel valence tautomeric cobalt complex, [Co(3,5-dbbq)2(μ-bpym)] (1) (3,5-dbbq = 3,5-di-tert-butyl-1,2-benzoquinone and μ-bpym = 2,2'-bipyrimidine). The synthesis is performed by reacting Co2(CO)8 and μ-bpym in the presence of the ligand 3,5-dbbq in a mixed solvent under inert atmosphere. The magnetic behavior clearly shows the presence of electron transfer from the catecholate ligand to the cobalt center, producing valence tautomers of [Co(II)(SQ)2] with a transition temperature (T1/2) of 215 K. Photomagnetic studies, performed via both SQUID magnetometry and X-band electron paramagnetic resonance, show the clear presence of photoinduced valence tautomerism, at temperatures considerably higher than previous systems. A metastable charge distribution is observed, strengthening previous investigations on the character of mixed valence ligands. Entropy-driven valence tautomeric interconversion is observed, and drives the transition to the most stable charge distribution. The complex has the ability to coordinate and can be used as a photoswitchable building block, with the photomagnetic characterisation evidencing a metastable state lifetime of the photo-induced valence tautomeric process of ca. 2.9 × 10(4) s below 20 K. The observed yields are higher than ones in similar systems, showing that tiny changes in the molecular structures may have a huge impact. |
spellingShingle | Slota, M Blankenhorn, M Heintze, E Vu, M Hübner, R Bogani, L Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism |
title | Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism |
title_full | Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism |
title_fullStr | Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism |
title_full_unstemmed | Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism |
title_short | Photoswitchable stable charge-distributed states in a new cobalt complex exhibiting photo-induced valence tautomerism |
title_sort | photoswitchable stable charge distributed states in a new cobalt complex exhibiting photo induced valence tautomerism |
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