Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 21st October 2020 from 07:00 AM to 07:00 PM (BST).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 32, 2019
Previous Article Next Article

Sulphur–sulphur, sulphur–selenium, selenium–selenium and selenium–carbon bond activation using Fe3(CO)12: an unexpected formation of an Fe2(CO)6 complex containing a μ23-C,O,Se-ligand

Author affiliations

Abstract

Three diiron hexacarbonyl complexes containing dithiolato (5), diselenolato (6), and selenolato-thiolato ligands (7), respectively, have been prepared as [FeFe]-hydrogenase mimics. Treatment of Fe3(CO)12 with one equivalent of the corresponding 5-membered heterocycles 1, 3 and 4 in toluene at reflux afforded the corresponding complexes 5–7. The reaction of 5,5-bis(bromomethyl)-2,2-dimethyl-1,3-dioxane with in situ generated Na2Se2 results in the formation of 8,8-dimethyl-7,9-dioxa-2,3-diselenaspiro[4.5]decane (1) and traces of 7,7-dimethyl-6,8-dioxa-2-selenaspiro[3.4]nonane (2). Alternatively, 5,5-bis(bromomethyl)-2,2-dimethyl-1,3-dioxane reacts with in situ generated Na2Se yielding compound 2 in 26% yield. When Fe3(CO)12 reacts under reflux with the selenaspiro compound 2 in toluene, the unique diiron complex, [Fe2(CO)623-Se,C,O-SeCH2C7H12O2}] (8), is obtained as a result of an initial selenium–carbon bond activation. Compounds 5, 6, 7, and 8 were characterized by IR, 1H, 13C{1H}, and 77Se{1H} NMR spectroscopy, mass spectrometry, elemental analysis, and X-ray single-crystal structure analysis. The chiral complex 8 shows a coordination of the O atom at the dioxane ring to one Fe atom and the O–CH carbanionic group to the other Fe atom. Furthermore, we investigated the redox properties and the catalytic behaviour of complexes 5–8 in the presence of AcOH as a source of protons. The reduction of complexes 5–7 is accompanied by a chemical process resulting in an overall two-electron transfer at their primary reduction wave. This observation is consistent with an ECE reduction (E = electrochemical process, C = chemical process), while each reduction event in the case of complex 8 involves simple transfer of one electron. Moreover, high level DFT calculations were performed on neutral 8 and its reduction products 8 and 82−.

Graphical abstract: Sulphur–sulphur, sulphur–selenium, selenium–selenium and selenium–carbon bond activation using Fe3(CO)12: an unexpected formation of an Fe2(CO)6 complex containing a μ2,κ3-C,O,Se-ligand

Back to tab navigation

Supplementary files

Article information


Submitted
21 May 2019
Accepted
01 Jul 2019
First published
02 Jul 2019

New J. Chem., 2019,43, 12580-12593
Article type
Paper

Sulphur–sulphur, sulphur–selenium, selenium–selenium and selenium–carbon bond activation using Fe3(CO)12: an unexpected formation of an Fe2(CO)6 complex containing a μ23-C,O,Se-ligand

R. Trautwein, H. Abul-Futouh, H. Görls, W. Imhof, L. R. Almazahreh and W. Weigand, New J. Chem., 2019, 43, 12580
DOI: 10.1039/C9NJ02642H

Social activity

Search articles by author

Spotlight

Advertisements