ポルフィリン金属錯体を用いた分子ワイヤー、およびポルフィリン多量体の合成研究

首都大学東京, 2015-09-30, 博士（理学）, 甲第556号首都大学東

Reactivity of the triruthenium ortho-metalated cluster [Ru-3(CO)(9){mu(3)- eta(1), kappa(1),kappa(2)-PhP( C6H4) CH2PPh}] with tri(2-thienyl) phosphine and tri( 2-furyl) phosphine: Formation of 1,3-diphenyl-2,3-dihydro-1H-1,3-benzodiphosphine complexes via phosphorus-carbon bond formation

Reaction of [Ru(CO)(9){mu(3-)eta(1),kappa(1),kappa(2)-PhP(C6H4)CH2PPh}] (1) with tri(2-thienyl) phosphine (PTh3) in refluxing THF afforded [Ru-3(CO)(9)(PTh3)(mu-dpbm)] (3){dpbm = PhP(C6H4)(CH2)PPh} and [Ru-3(CO)(6)(mu-CO)(2){mu-kappa(1),eta(1)-PTh2(C4H2S)}{mu(3)-kappa(1),ka ppa(2)-Ph2PCH2PPh}] (5) in 18% and 12% yields, respectively, while a similar reaction with tri(2-furyl)phosphine (PFu(3)) gave [Ru-3(CO)(9)(PFu(3))(mu-dpbm)] (4) and [Ru-3(CO)(7)(mu-eta(1),eta(2)-C4H3O)(mu-PFu(2)){mu(3)-eta(1),kappa(1),ka ppa(2)-PhP(C6H4)CH2PPh}] (6) in 24% and 27% yields, respectively. Compounds 2 and 4 are phosphine adducts of 1 in which the diphosphine ligand is transformed into 1,3-diphenyl-2,3-dihydro-1H-1,3-benzodiphosphine(dpbm) via phosphorus-carbon bond formation. Cluster 5 results from metalation of a thienyl ring, the cleved proton being transfoerred to the diphosphine.Carbon-phosphorus bond clevarge of a PFu(3) ligand is observed in 6 to afford a phosphido-bridge and furyl fragment, the latter bridging in a sigma,pi-vinyl fashion. The molecular strucutres of 3,5 and 6 have been determined by X-ray diffraction studies. (C) 2009 Published by Elsevier B.V

Hydrogenase Biomimetics with Redox-Active Ligands: Synthesis, Structure, and Electrocatalytic Studies on [Fe₂(CO)₄(κ²-dppn)(µ-edt)] (edt = Ethanedithiolate; dppn = 1,8-bis(Diphenylphosphino)Naphthalene)

Addition of the bulky redox-active diphosphine 1,8-bis(diphenylphosphino)naphthalene (dppn) to [Fe2(CO)6(µ-edt)] (1) (edt = 1,2-ethanedithiolate) affords [Fe2(CO)4(κ2-dppn)(µ-edt)] (3) as the major product, together with small amounts of a P⁻C bond cleavage product [Fe2(CO)5{κ1-PPh2(1-C10H7)}(µ-edt)] (2). The redox properties of 3 have been examined by cyclic voltammetry and it has been tested as a proton-reduction catalyst. It undergoes a reversible reduction at E1/2 = −2.18 V and exhibits two overlapping reversible oxidations at E1/2 = −0.08 V and E1/2 = 0.04 V. DFT calculations show that while the Highest Occupied Molecular Orbital (HOMO) is metal-centred (Fe⁻Fe σ-bonding), the Lowest Unoccupied Molecular Orbital (LUMO) is primarily ligand-based, but also contains an antibonding Fe⁻Fe contribution, highlighting the redox-active nature of the diphosphine. It is readily protonated upon addition of strong acids and catalyzes the electrochemical reduction of protons at Ep = −2.00 V in the presence of CF3CO2H. The catalytic current indicates that it is one of the most efficient diiron electrocatalysts for the reduction of protons, albeit operating at quite a negative potential

An Overview of Diabetic Foot Ulcers and Associated Problems with Special Emphasis on Treatments with Antimicrobials

One of the most significant challenges of diabetes health care is diabetic foot ulcers (DFU). DFUs are more challenging to cure, and this is particularly true for people who already have a compromised immune system. Pathogenic bacteria and fungi are becoming more resistant to antibiotics, so they may be unable to fight microbial infections at the wound site with the antibiotics we have now. This article discusses the dressings, topical antibacterial treatment, medications and debridement techniques used for DFU and provides a deep discussion of DFU and its associated problems. English-language publications on DFU were gathered from many different databases, such as Scopus, Web of Science, Science Direct, Springer Nature, and Google Scholar. For the treatment of DFU, a multidisciplinary approach involving the use of diagnostic equipment, skills, and experience is required. Preventing amputations starts with patient education and the implementation of new categorization systems. The microbiota involved in DFU can be better understood using novel diagnostic techniques, such as the 16S-ribosomal DNA sequence in bacteria. This could be achieved by using new biological and molecular treatments that have been shown to help prevent infections, to control local inflammation, and to improve the healing process