1185907-11-2Relevant academic research and scientific papers
Hydrido copper clusters supported by dithiocarbamates: Oxidative hydride removal and neutron diffraction analysis of [Cu7(H){S 2C(aza-15-crown-5)}6]
Liao, Ping-Kuei,Fang, Ching-Shiang,Edwards, Alison J.,Kahlal, Samia,Saillard, Jean-Yves,Liu
, p. 6577 - 6591 (2012)
Reactions of Cu(I) salts with Na(S2CR) (R = NnPr 2, NEt2, aza-15-crown-5), and (Bu4N)(BH 4) in an 8:6:1 ratio in CH3CN solution at room temperature yield the monocationic hydride-centered octanuclear CuI clusters, [Cu8(H){S2CR}6](PF6) (R = N nPr2, 1H; NEt2, 2H; aza-15-crown-5, 3H). Further reactions of [Cu8(H){S 2CR}6](PF6) with 1 equiv of (Bu 4N)(BH4) produced neutral heptanuclear copper clusters, [Cu7(H){S2CR}6] (R = NnPr 2, 4H; NEt2, 5H; aza-15-crown-5, 6H) and clusters 4-6 can also be generated from the reaction of Cu(BF4)2, Na(S2CR), and (Bu4N) (BH4) in a 7:6:8 molar ratio in CH3CN. Reformation of cationic CuI8 clusters by adding 1 equiv of CuI salt to the neutral Cu7 clusters in solution is observed. Intriguingly, the central hydride in [Cu8(H){S2CN nPr2}6](PF6) can be oxidatively removed as H2 by Ce(NO3)62- to yield [CuII(S2CNnPr2)2] exploiting the redox-tolerant nature of dithiocarbamates. Regeneration of hydride-centered octanuclear copper clusters from the [CuII(S 2CNnPr2)2] can be achieved by reaction with Cu(I) ions and borohydride. The hydride release and regeneration of CuI8 was monitored by UV-visible titration experiments. To our knowledge, this is the first time that hydride encapsulated within a copper cluster can be released as H2 via chemical means. All complexes have been fully characterized by 1H NMR, FT-IR, UV-vis, and elemental analysis, and molecular structures of 1H, 2H, and 6H were clearly established by single-crystal X-ray diffraction. Both 1H and 2H exhibit a tetracapped tetrahedral Cu 8 skeleton, which is inscribed within a S12 icosahedron constituted by six dialkyl dithiocarbamate ligands in a tetrametallic- tetraconnective (μ2, μ2) bonding mode. The copper framework of 6H is a tricapped distorted tetrahedron in which the four-coordinate hydride is demonstrated to occupy the central site by single crystal neutron diffraction. Compounds 1-3 exhibit a yellow emission in both the solid state and in solution under UV irradiation at 77 K, and the structureless emission is assigned as a 3metal to ligand charge transfer (MLCT) excited state. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations on model compounds match the experimental structures and provide rationalization of their bonding and optical properties.
A bifunctional diketimine ligand for secondary building blocks: Formation of a 2D copper-zinc coordination polymer
Rousset, A,Whitehorne, Todd J. J.,Baslon, Valerie,Reber, Christian,Schaper, Frank
, p. 331 - 335 (2011/05/07)
Condensation of 3-(aminomethyl)pyridine with acetylacetone in the presence of 2 equiv. of HCl affordedN,Na'-bis(3-pyridylmethyl)-2-amino-4-imino-pent-2- ene, nacnacCH2PyH, a diketimine with pendant pyridine donors.Under the same conditions, 2- and 4-(aminomethyl)pyridine afforded the respective 1-(2-pyridyl)- and 1-(4-pyridyl)-2,4-dimethylpyrrol. The heteroleptic complex (nacnacCH2Py)(nacnacBn)Zn was obtained upon reaction of nacnacCH2PyH with nacnacBnZnEt. Combining 2 equiv. of this ligand with ZnEt2 afforded the homoleptic complex nacnac CH2Py2Zn. The latter forms a 2D coordination polymer upon reaction with [Cu(NCMe)4][PF6], which shows short-lived luminescence at ambient temperature. The coordination polymer and complex (nacnacCH2Py)(nacnacBn)Zn were characterised by single-crystal X-ray diffraction. Zinc complexes of a new bifunctional diketimine ligand with pendant pyridine donor ligands can serve as building blocks for polynuclear or supramolecular assemblies.Reaction of the building block with CuI cations affords a bimetallic, luminescent Cu-Zn coordination polymer. Copyright
Cap for copper(I) ions! metallosupramolecular solid and solution state structures on the basis of the dynamic tetrahedral [Cu(phenAr 2)(py)2]+ motif
Schmittel, Michael,He, Bice,Fan, Jian,Bats, Jan W.,Engeser, Marianne,Schlosser, Marc,Deiseroth, Hans-Joerg
, p. 8192 - 8200 (2009/12/08)
The tetrahedral [Cu(phenAr2)(py)2]+ coordination motif (phen = 1,10-phenanthroline; py = pyridine) conceived on the basis of the HETPYP concept (heteroleptic pyridyl and phenanthroline metal complexes) is a versatile dynam
Copper Complexes as Functional Models for Dopamine β-Hydroxylase. Mechanistic Study of Oxygen Atom Transfer from Cu/O Species to Benzylic C-Bonds
Blain, Ingrid,Giorgi, Michel,Riggi, Innocenzo De,Reglier, Marius
, p. 205 - 212 (2007/10/03)
The mechanism of the oxygen atom transfer reaction mediated by copper-oxygen species has been studied through a substrate-binding ligand approach. Oxidations of copper 5-X-IndPY2 type complexes in which an electron donating (X = OMe) or withdrawing group (X = CN) substitutes the aromatic nucleus in position 5, lead to compounds 2b,c and 3b,c resulting from benzylic hydroxylations. With these complexes, where one of the benzylic positions is influenced by a para substituent (leading to 2b,c) while the other suffers influence from the meta group (leading to 3b,c), we observe that the ratio 2:3 > 1 is in favor of a certain electrophilicity of the copper/oxygen species responsible for the hydroxylations. While a concerted mechanism cannot be excluded, the results are in favor of a two-step mechanism involving radical species.
