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  1. AU="Manassero, Carlo"
  2. AU="Kirk, Tom"
  3. AU="Bezabih, Yihienew Mequanint"
  4. AU="Hirsinger, Estelle"
  5. AU="Robles-Musso Castillo, Emilio"
  6. AU="Vahdatihassani, Faezeh"
  7. AU="Maria Pala"
  8. AU=Singh Indra
  9. AU="Gallacher, Nicola"
  10. AU="Chen, Pei-Min"
  11. AU=Andre L
  12. AU="Aleksandra I. Pivovarova"
  13. AU="Cruz, Thainá Gabriele Camargo da"
  14. AU="Atkins, Peter"

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  1. Artikel ; Online: Cooperation between cis and trans influences in cis-Pt(II)(PPh(3))(2) complexes: structural, spectroscopic, and computational studies.

    Rigamonti, Luca / Forni, Alessandra / Manassero, Mario / Manassero, Carlo / Pasini, Alessandro

    Inorganic chemistry

    2010  Band 49, Heft 1, Seite(n) 123–135

    Abstract: The relevance of cis and trans influences of some anionic ligands X and Y in cis-[PtX(2)(PPh(3))(2)] and cis-[PtXY(PPh(3))(2)] complexes have been studied by the X-ray crystal structures of several derivatives (X(2) = (AcO)(2) (3), (NO(3))(2) (5), Br(2) ( ...

    Abstract The relevance of cis and trans influences of some anionic ligands X and Y in cis-[PtX(2)(PPh(3))(2)] and cis-[PtXY(PPh(3))(2)] complexes have been studied by the X-ray crystal structures of several derivatives (X(2) = (AcO)(2) (3), (NO(3))(2) (5), Br(2) (7), I(2) (11); and XY = Cl(AcO) (2), Cl(NO(3)) (4), and Cl(NO(2)) (13)), density functional theory (DFT) calculations, and one bond Pt-P coupling constants, (1)J(PtP). The latter have allowed an evaluation of the relative magnitude of both influences. It is concluded that such influences act in a cooperative way and that the cis influence is not irrelevant when rationalizing the (1)J(PtP) values, as well as the experimental Pt-P bond distances. On the contrary, in the optimized geometries, evaluated through B3LYP/def2-SVP calculations, the cis influence was not observed, except for compounds ClPh (21), Ph(2) (22), and, to a lesser extent, Cl(NO(2)) (13) and (NO(2))(2) (14). A natural bond order analysis on the optimized structures, however, has shown how the cis influence can be related to the s-character of the Pt hybrid orbital involved in the Pt-P bonds and the net atomic charge on Pt. We have also found that in the X-ray structures of cis-[PtX(2)(PPh(3))(2)] complexes the two Pt-X and the two Pt-P bond lengths are different each other and are related to the conformation of the phosphine groups, rather than to the crystal packing, since this feature is observed also in the optimized geometries.
    Sprache Englisch
    Erscheinungsdatum 2010-01-04
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1484438-2
    ISSN 1520-510X ; 0020-1669
    ISSN (online) 1520-510X
    ISSN 0020-1669
    DOI 10.1021/ic901510m
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: Cis influence in trans-Pt(PPh3)2 complexes.

    Rigamonti, Luca / Manassero, Carlo / Rusconi, Michele / Manassero, Mario / Pasini, Alessandro

    Dalton transactions (Cambridge, England : 2003)

    2009  , Heft 7, Seite(n) 1206–1213

    Abstract: The cis influence of a series of anionic ligands X and Y has been evaluated through the magnitude of the Pt-P coupling constants for compounds of formula trans-[PtXY(PPh(3))(2)]. The order of decreasing cis influence was found to be I > Cl > SePh ... ...

    Abstract The cis influence of a series of anionic ligands X and Y has been evaluated through the magnitude of the Pt-P coupling constants for compounds of formula trans-[PtXY(PPh(3))(2)]. The order of decreasing cis influence was found to be I > Cl > SePh approximately SPh approximately SEt > NO(3) > AcO approximately NO(2) > H > Me > Ph > mtc (mtc = N,N-dimethylmonothiocarbamato-S); moreover, the cis influences of the various ligands was found to be additive. The X-ray structures of three representative compounds (t-: X = Cl, Y = NO(3); t-: X = Cl, Y = AcO and t-: X = Y = NO(2)) have also been determined.
    Sprache Englisch
    Erscheinungsdatum 2009-02-21
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 1472887-4
    ISSN 1364-5447 ; 1477-9234 ; 1477-9226 ; 0300-9246
    ISSN (online) 1364-5447 ; 1477-9234
    ISSN 1477-9226 ; 0300-9246
    DOI 10.1039/b813125b
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Structural variations, electrochemical properties and computational studies on monomeric and dimeric Fe-Cu carbide clusters, forming copper-based staple arrays.

    Della Pergola, Roberto / Bruschi, Maurizio / Sironi, Annalisa / Manassero, Mario / Manassero, Carlo / Strumolo, Donatella / Fedi, Serena / Zanello, Piero

    Dalton transactions (Cambridge, England : 2003)

    2011  Band 40, Heft 20, Seite(n) 5464–5475

    Abstract: The halide ligands of [Fe(4)C(CO)(12)(CuCl)(2)](2-) (1) and [Fe(5)C(CO)(14)CuCl](2-) (2) can be displaced by N-, P- or S-donors. Beside substitution, the clusters easily undergo structural rearrangements, with loss/gain of metal atoms, and formation of ... ...

    Abstract The halide ligands of [Fe(4)C(CO)(12)(CuCl)(2)](2-) (1) and [Fe(5)C(CO)(14)CuCl](2-) (2) can be displaced by N-, P- or S-donors. Beside substitution, the clusters easily undergo structural rearrangements, with loss/gain of metal atoms, and formation of Fe(4)Cu/Fe(4)Cu(3) metallic frameworks. Thus, the reaction of 1 with excess dppe yielded [{Fe(4)C(CO)(12)Cu}(2)(μ-dppe)](2-) (3). [{Fe(4)C(CO)(12)Cu}(2)(μ-pyz)](2-) (4) was obtained by reaction of 2 with Ag(+) and pyrazine. [Fe(4)C(CO)(12)Cu-py](-) (5) was formed more directly from [Fe(4)C(CO)(12)](2-), [Cu(NCMe)(4)](+) and pyridine. [Fe(4)Cu(3)C(CO)(12)(μ-S(2)CNEt(2))(2)](-) (6) and [{Fe(4)Cu(3)C(CO)(12)(μ-pz)(2)}(2)](2-) (7) were prepared by substitution of the halides of 1 with diethyldithiocarbamate and pyrazolate, in the presence of Cu(i) ions. All of these products were characterized by X-ray analysis. 3 and 4 and 5 are square based pyramids, with iron in the apical sites, the bridging ligands connect the two copper atoms in 3 and 4. 6 and 7 are octahedral clusters with an additional copper ion held in place by the two bridging anionic ligands, forming a Cu(3) triangle with Cu-Cu distances ranging 2.63-3.13 Å. In 7, an additional unbridged cuprophilic interaction (2.75 Å) is formed between two such cluster units. DFT calculations were able to reproduce the structural deformations of 3-5, and related their differences to the back-donation from the ligand to Cu. Additionally, DFT found that, in solution, the tight ion pair [NEt(4)](2)7 is almost isoenergetic with the monomeric form. Thus, 3, 4 and 7 are entities of nanometric size, assembled either through conventional metal-ligand bonds or weaker electrostatic interactions. None of them allows electronic communication between the two monomeric units, as shown by electrochemistry and spectroelectrochemical studies. (dppe = PPh(2)CH(2)CH(2)PPh(2), pyz = pyrazine C(4)N(2)H(4), py = pyridine C(5)H(5)N, pz = pyrazolate C(3)N(2)H(3)(-)).
    Sprache Englisch
    Erscheinungsdatum 2011-05-28
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 1472887-4
    ISSN 1477-9234 ; 1364-5447 ; 0300-9246 ; 1477-9226
    ISSN (online) 1477-9234 ; 1364-5447
    ISSN 0300-9246 ; 1477-9226
    DOI 10.1039/c0dt01766c
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel ; Online: Gold(III) six-membered N^C^N pincer complexes: synthesis, structure, reactivity and theoretical calculations.

    Alesso, Giuseppe / Cinellu, Maria Agostina / Stoccoro, Sergio / Zucca, Antonio / Minghetti, Giovanni / Manassero, Carlo / Rizzato, Silvia / Swang, Ole / Ghosh, Manik Kumer

    Dalton transactions (Cambridge, England : 2003)

    2010  Band 39, Heft 42, Seite(n) 10293–10304

    Abstract: The first six-membered gold(III) N^C^N pincer complex was obtained in good yield, under very mild conditions, by transmetalation of [Hg(κC-N^C^N)Cl] (N^CH^N = 1,3-bis(pyridin-2-ylmethyl)benzene, HL(1)) with Na[AuCl(4)]. The X-ray crystal structure of [Au( ...

    Abstract The first six-membered gold(III) N^C^N pincer complex was obtained in good yield, under very mild conditions, by transmetalation of [Hg(κC-N^C^N)Cl] (N^CH^N = 1,3-bis(pyridin-2-ylmethyl)benzene, HL(1)) with Na[AuCl(4)]. The X-ray crystal structure of [Au(N^C^N)Cl][PF(6)] showed that the fused six-membered metallacycles each exist in a strongly puckered boat conformation. As shown by the (1)H NMR spectra in various solvents, the same structure is also retained in solution: no inversion of the six-membered metallacycles is observed in DMSO up to 95 °C. This correlates well with a reaction barrier of 17.5 kcal/mole, as determined by quantum chemical calculations. The reactivity of the present pincer complex is compared to that of the analogous 1,3-bis(2-pyridyl)benzene, HL(2), derivative, which has five-membered fused metallacycles. Sharp differences are found in the reactions with phosphines, such as PPh(3) and dppe (1,2-bis-diphenylphosphino-ethane), and with silver salts. Theoretical calculations were carried out on the two pincer complexes in order to try to understand these differences, and we found that the gold-chlorine bond is significantly stronger in the case of the complex containing five-membered metallacyclic rings.
    Mesh-Begriff(e) Carbon/chemistry ; Crystallography, X-Ray ; Gold/chemistry ; Magnetic Resonance Spectroscopy ; Nitrogen/chemistry ; Organometallic Compounds/chemical synthesis ; Organometallic Compounds/chemistry ; Quantum Theory
    Chemische Substanzen Organometallic Compounds ; Carbon (7440-44-0) ; Gold (7440-57-5) ; Nitrogen (N762921K75)
    Sprache Englisch
    Erscheinungsdatum 2010-11-14
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1472887-4
    ISSN 1477-9234 ; 1364-5447 ; 0300-9246 ; 1477-9226
    ISSN (online) 1477-9234 ; 1364-5447
    ISSN 0300-9246 ; 1477-9226
    DOI 10.1039/c0dt00705f
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Artikel: A traditional synthetic method, and a new structural motif, for molybdenum-gold clusters: synthesis and solid-state structure of Au8{Mo(CO)5}4(PPh3)4.

    Della Pergola, Roberto / Garlaschelli, Luigi / Malatesta, Maria Carlotta / Manassero, Carlo / Manassero, Mario

    Inorganic chemistry

    2006  Band 45, Heft 21, Seite(n) 8465–8467

    Abstract: The neutral cluster [Au8Mo4(CO)20(PPh3)4] was synthesized in low yield from [AuCl(PPh3)] and [Mo2(CO)10]2- in acetonitrile at room temperature. The cluster was characterized by X-ray analysis, IR, and 31P NMR spectroscopy. Its solid-state structure ... ...

    Abstract The neutral cluster [Au8Mo4(CO)20(PPh3)4] was synthesized in low yield from [AuCl(PPh3)] and [Mo2(CO)10]2- in acetonitrile at room temperature. The cluster was characterized by X-ray analysis, IR, and 31P NMR spectroscopy. Its solid-state structure consists of four Au(3)Mo tetrahedral units, fused by four Au atoms in a ring. The average bond lengths are Au-Au 2.77 Angstrom and Mo-Au 2.93 Angstrom. The internal angles of the planar square ring are very close to 90 degrees.
    Mesh-Begriff(e) Acetonitriles ; Gold Compounds/chemistry ; Magnetic Resonance Spectroscopy/methods ; Molecular Conformation ; Molybdenum/chemistry
    Chemische Substanzen Acetonitriles ; Gold Compounds ; Molybdenum (81AH48963U) ; acetonitrile (Z072SB282N)
    Sprache Englisch
    Erscheinungsdatum 2006-10-16
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1484438-2
    ISSN 1520-510X ; 0020-1669
    ISSN (online) 1520-510X
    ISSN 0020-1669
    DOI 10.1021/ic060524l
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel: Reactivity of 1,3-bis(2-pyridyl)benzene, N--CH--N, with gold(III) chlorides: salts, adducts and cyclometalated pincer derivatives. Crystal and molecular structures of [HN--CH--N][AuCl4], [Au(N--C--N)Cl][PF6] and [Au(N--C--N)Cl(PPh3)2][PF6].

    Stoccoro, Sergio / Alesso, Giuseppe / Cinellu, Maria Agostina / Minghetti, Giovanni / Zucca, Antonio / Manassero, Mario / Manassero, Carlo

    Dalton transactions (Cambridge, England : 2003)

    2009  , Heft 18, Seite(n) 3467–3477

    Abstract: The reaction of 1,3-bis(2-pyridyl)benzene, N--CH--N, with H[AuCl(4)] has been studied under different conditions. Mono- ([N--CH--NH][AuCl(4)]) and di-protonated salts ([HN--CH--NH][AuCl(4)](2)), as well as an adduct, [(N--CH--N)(AuCl(3))(2)], have been ... ...

    Abstract The reaction of 1,3-bis(2-pyridyl)benzene, N--CH--N, with H[AuCl(4)] has been studied under different conditions. Mono- ([N--CH--NH][AuCl(4)]) and di-protonated salts ([HN--CH--NH][AuCl(4)](2)), as well as an adduct, [(N--CH--N)(AuCl(3))(2)], have been isolated. Very rare cyclometalated pincer derivatives, [Au(N--C--N)Cl](+) have been obtained as different salts, either by transmetallation from the corresponding mercury(ii) derivative, [Hg(N--C--N)Cl], or by direct C-H activation. The structures in the solid state of [N--CH--NH][AuCl(4)] and [Au(N--C--N)Cl][PF(6)] have been solved by X-ray diffraction. Reaction of the pincer derivatives with PPh(3), dppm (bis(diphenylphosphino)methane) and dppe (1,2-bis(diphenylphosphino)ethane) occurs with displacement of the coordinated nitrogen atoms to afford [Au(N--C--N)(Cl)(PPh(3))(2)](+), [Au(N--C--N)(Cl)(dppm)(2)](+) and [Au(N--C--N)(Cl)(dppe)](+), respectively. The X-ray structure of [Au(N--C--N)(Cl)(PPh(3))(2)][PF(6)] confirms that the ligand N--C--N is only sigma-carbon bonded and the PPh(3) molecules are in a trans-arrangement. The pattern of the (31)P{(1)H}NMR spectrum of [Au(N--C--N)(Cl)(dppm)(2)](+), a pair of "triplets", deserves comments: the spectrum is not of the A(2)X(2) type but a case of a deceptively simple AA'XX' spin system.
    Sprache Englisch
    Erscheinungsdatum 2009-05-14
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 1472887-4
    ISSN 1364-5447 ; 1477-9234 ; 1477-9226 ; 0300-9246
    ISSN (online) 1364-5447 ; 1477-9234
    ISSN 1477-9226 ; 0300-9246
    DOI 10.1039/b822842f
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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