935552-37-7Relevant articles and documents
Diiron hexacarbonyl complexes bearing naphthalene-1,8-dithiolate bridge moiety as mimics of the sub-unit of [FeFe]-hydrogenase: Synthesis, characterisation and electrochemical investigations
Qian, Guifen,Zhong, Wei,Wei, Zhenhong,Wang, Hailong,Xiao, Zhiyin,Long, Li,Liu, Xiaoming
, p. 9752 - 9760 (2015)
Eight diiron hexacarbonyl complexes bearing a 1,8-dithionaphthalenyl bridging linkage as mimics of the diiron subunit of [FeFe]-hydrogenase are reported. Reaction of Fe3(CO)12 with naphtha[1,8-cd][1,2]dithiole-n-carbaldehyde (n = 2: 2a or 4: 2b) gave two complexes, [Fe2(μ-S)2R(CO)6] (-SRS- = n-formylnaphthalene-1,8-bis(thiolate), n = 2: 3a, 4: 3b), which were further used as precursors to prepare six other complexes by manipulating the formyl groups. Converting the corresponding formyl group into a hydroxymethyl group (CH2OH) led to complexes 4a and 4b. Their reactions with halobutanoyl chloride formed complexes 5a and 5b (halo group = Cl), and 6a and 6b (halo group = Br), respectively. Among the complexes, 3a, 3b, 4b, 5b, and 6a were crystallographically analysed. Electrochemical investigations into these complexes revealed that the formyl group exerts profound electronic influence on the electrochemistry, and thus catalysis of proton reduction, due to its involvement in the conjugation of the bridging linkage. DFT calculations indicate that the formyl group influences the electrochemistry and catalysis by significantly altering the composition of the LUMOs.
The influence of a peripheral functional group of diiron hexacarbonyl complexes on their electrochemistry and electrocatalytic reduction of proton
Zhong, Wei,Xiao, Zhiyin,Qian, Guifen,Liu, Xiaoming
, p. 779 - 786 (2017)
Three diiron hexacarbonyl complexes (2, 3 and 4) with naphthalene-1,8-bis(thiolate) skeleton as their bridging linkages are reported. For comparison, the protonated form of complex 4 was also prepared (4H+). They bear respectively a functional group on the naphthalene ring at the position 2, i.e. ?CH2OH (2), ?COOH (3), ?CH2N(Et)2 (4) and ?CH2NH+(Et)2 (4H+). Complex 2 was derived from the direct reduction of its precursor bearing aldehyde group (?CHO, 1) by NaBH4 while complexes 3 and 4 were routinely synthesized by reacting Fe3(CO)12 with ligands L2 and L3, respectively, which were derived from ligand L1, naphtho[1,8-cd][1,2]dithiole-3-carbaldehyde. These complexes were fully characterized and complexes 3 and 4 were analyzed using X-ray single crystal diffraction. Electrochemistry of these complexes was also investigated by cyclic voltammetry. The carboxylic acid of complex 3 shows significant influence on the second reduction due to the acid group involving reaction with the reduced species. Both infrared spectral data and the first reduction potentials of the complexes suggest that these functional groups exert hardly electronic influence on the metal center. However, the functional groups which can carry proton (?COOH and ?CH2N+H(Et)2) can ease the kinetics of the catalysis of proton reduction via probably PCET (proton-coupled electron transfer) mechanism. These proton carriers can also improve catalytic efficiency by acting a proton relay during the catalysis as suggested by the linear plots of peak current against acid concentration for the three complexes.
Deiodination of thyroid hormones by iodothyronine deiodinase mimics: Does an increase in the reactivity alter the regioselectivity?
Manna, Debasish,Mugesh, Govindasamy
supporting information; scheme or table, p. 9980 - 9983 (2011/08/21)
Organoselenium compounds as functional mimics of iodothyronine deiodinase are described. The naphthyl-based compounds having two selenol groups are remarkably efficient in the inner-ring deiodination of thyroxine. The introduction of a basic amino group in close proximity to one of the selenol moieties enhances the deiodination. This study suggests that an increase in the nucleophilic reactivity of the conserved Cys residue at the active site of deiodinases is very important for effective deiodination.