Thiolate-bridged dinuclear iron(tris-carbonyl)-nickel complexes relevant to the active site of [NiFe] hydrogenase
| Autor: | Kazuyuki Tatsumi, Zilong Li, Kazunari Yasumura, Yasuhiro Ohki, Soichiro Tanino, Katsuaki Kuge, Masaru Ando |
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| Rok vydání: | 2008 |
| Předmět: |
Hydrogenase
Stereochemistry chemistry.chemical_element Medicinal chemistry Ferric Compounds law.invention chemistry.chemical_compound law Nickel Organometallic Compounds Molecule Sulfhydryl Compounds Crystallization Coordination geometry Multidisciplinary Binding Sites biology Molecular Structure Chemistry Active site Octahedron Physical Sciences biology.protein Methanol |
| Zdroj: | Proceedings of the National Academy of Sciences of the United States of America. 105(22) |
| ISSN: | 1091-6490 |
| Popis: | The reaction of NiBr 2 (EtOH) 4 with a 1:2–3 mixture of FeBr 2 (CO) 4 and Na(SPh) generated a linear trinuclear Fe–Ni–Fe cluster (CO) 3 Fe(μ-SPh) 3 Ni(μ-SPh) 3 Fe(CO) 3 , 1, whereas the analogous reaction system FeBr 2 (CO) 4 /Na(S t Bu)/NiBr 2 (EtOH) 4 (1:2–3:1) gave rise to a linear tetranuclear Fe–Ni–Ni–Fe cluster [(CO) 3 Fe(μ-S t Bu) 3 Ni(μ-Br)] 2 , 2. By using this tetranuclear cluster 2 as the precursor, we have developed a new synthetic route to a series of thiolate-bridged dinuclear Fe(CO) 3 –Ni complexes, the structures of which mimic [NiFe] hydrogenase active sites. The reactions of 2 with SC(NMe 2 ) 2 (tmtu), Na{S(CH 2 ) 2 SMe} and ortho -NaS(C 6 H 4 )SR (R = Me, t Bu) led to isolation of (CO) 3 Fe(μ-S t Bu) 3 NiBr(tmtu), 3, (CO) 3 Fe(S t Bu)(μ-S t Bu) 2 Ni{S(CH 2 ) 2 SMe}, 4, and (CO) 3 Fe(S t Bu)(μ-S t Bu) 2 Ni{S(C 6 H 4 )SR}, 5a (R = Me) and 5b (R = t Bu), respectively. On the other hand, treatment of 2 with 2-methylthio-phenolate ( ortho -O(C 6 H 4 )SMe) in methanol resulted in (CO) 3 Fe(μ-S t Bu) 3 Ni(MeOH){O(C 6 H 4 )SMe}, 6a. The methanol molecule bound to Ni is labile and is readily released under reduced pressure to afford (CO) 3 Fe(S t Bu)(μ-S t Bu) 2 Ni{O(C 6 H 4 )SMe}, 6b, and the coordination geometry of nickel changes from octahedral to square planar. Likewise, the reaction of 2 with NaOAc in methanol followed by crystallization from THF gave (CO) 3 Fe(μ-S t Bu) 3 Ni(THF)(OAc), 7. The dinuclear complexes, 3-7, are thermally unstable, and a key to their successful isolation is to carry out the reactions and manipulations at −40°C. |
| Databáze: | OpenAIRE |
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