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141.
M.F. Corrigan G.B. Deacon B.O. West D.G. Vince 《Journal of organometallic chemistry》1976,105(1):119-125
The complexes RCo(acacen) [R = C6F5, p-HC6F4, or o-HC6F4; H2acacen = N,N′-ethylenebis(acetylacetonimine)] and RCo(salen) [R = C6F5 or p-HC6F4; H2salen = N,N′-ethylenebis(salicylaldimine)] have been prepared by reaction between Co(acacen) or Co(salen) and the appropriate bromobis(polyfluorophenyl)thallium(III) compounds, and have been isolated as pyridinates. Spectroscopic evidence for formation of C6F5Co(salophen) [H2salophen = N,N′-o-phenylenebis(salicylaldimine)] has also been obtained. The reactivity of the thallium compounds increased in the sequence Ph2TlBr ? (o-HC6F4)2TlBr < (p-HC6F4)2TlBr < (C6F5)2TlBr, and of the cobalt complexes in the sequence Co(salophen) < Co(salen) < Co(acacen). Possible mechanisms are discussed. 相似文献
142.
The reaction of [Sm{N(SiMe3)2}2(THF)2] (THF=tetrahydrofuran) with carbodiimides RN=C=NR (R=Cy, C6H3-2,6-iPr2) led to the formation of dinuclear SmIII complexes via differing C-C coupling processes. For R=Cy, the product [{(Me3Si)2N}2Sm(micro-C2N4Cy4)Sm{N(SiMe3)2}2] (1) has an oxalamidinate [C2N4Cy4]2- ligand resulting from coupling at the central C atoms of two CyNCNCy moieties. In contrast, for R=C6H3-2,6-iPr2, H transfer and an unusual coupling of two iPr methine C atoms resulted in a linked formamidinate complex, [{(Me3Si)2N}2Sm{micro-(RNC(H)N(Ar-Ar)NC(H)NR)}Sm{N(SiMe3)2}2] (2) (Ar-Ar=C6H3-2-iPr-6-C(CH3)2C(CH3)2-6'-C6H3-2'-iPr). Analogous reactions of RN=C=NR (R=Cy, C6H3-2,6-iPr2) with the SmII "ate" complex [Sm{N(SiMe2)3Na] gave 1 for R=Cy, but a novel C-substituted amidinate complex, [(THF)Na{N(R)C(NR)CH2Si(Me2)N(SiMe3)}Sm{N(SiMe3)2}2] (3), for R=C6H3-2,6-iPr2, via gamma C-H activation of a N(SiMe3)2 ligand. 相似文献
143.
Chesman AS Turner DR Price DJ Moubaraki B Murray KS Deacon GB Batten SR 《Chemical communications (Cambridge, England)》2007,(34):3541-3543
The formation of discrete complexes [M(mcoe)2S2] (M = Cu, Ni; S = MeOH, H2O) vs. a nitroso-bridged ferromagnetically-coupled Cu(II) coordination polymer [Cu(mcoe)2] is influenced by the use of solvothermal reaction conditions. 相似文献
144.
Cole ML Deacon GB Forsyth CM Junk PC Konstas K Wang J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(29):8092-8110
Reactions of a range of the readily prepared and sterically tunable N,N'-bis(aryl)formamidines with lanthanoid metals and bis(pentafluorophenyl)mercury (Hg(C6F5)2) in THF have given an extensive series of tris(formamidinato)lanthanoid(III) complexes, [Ln(Form)3(thf)n], namely [La(o-TolForm)3(thf)2], [Er(o-TolForm)3(thf)], [La(XylForm)3(thf)], [Sm(XylForm)3], [Ln(MesForm)3] (Ln=La, Nd, Sm and Yb), [Ln(EtForm)3] (Ln=La, Nd, Sm, Ho and Yb), and [Ln(o-PhPhForm)3] (Ln=La, Nd, Sm and Er). [For an explanation of the N,N'-bis(aryl)formamidinate abbreviations used see Scheme 1.] Analogous attempts to prepare [Yb(o-TolForm)3] by this method invariably yielded [{Yb(o-TolForm)2(mu-OH)(thf)}2], but [Yb(o-TolForm)3] was isolated from a metathesis synthesis. X-ray crystal structures show exclusively N,N'-chelation of the Form ligands and a gradation in coordination number with Ln3+ size and with Form ligand bulk. The largest ligands, MesForm, EtForm and o-PhPhForm give solely homoleptic complexes, the first two being six-coordinate, the last having an eta1-pi-Ar--Ln interaction. Reaction of lanthanoid elements and Hg(C6F5)2 with the still bulkier DippFormH in THF resulted in C--F activation and formation of [Ln(DippForm)2F(thf)] (Ln=La, Ce, Nd, Sm and Tm) complexes, and o-HC6F4O(CH2)4DippForm in which the formamidine is functionalised by a ring-opened THF that has trapped tetrafluorobenzyne. Analogous reactions between Ln metals, Hg(o-HC6F4)2 and DippFormH yielded [Ln(DippForm)2F(thf)] (Ln=La, Sm and Nd) and 3,4,5-F3C6H2O(CH2)4DippForm. X-ray crystal structures of the heteroleptic fluorides show six-coordinate monomers with two chelating DippForm ligands and cisoid fluoride and THF ligands in a trigonal prismatic array. The organometallic species [Ln(DippForm)2(C[triple chemical bond]CPh)(thf)] (Ln=Nd or Sm) are obtained from reaction of Nd metal, bis(phenylethynyl)mercury (Hg(C[triple chemical bond]CPh)2) and DippFormH, and the oxidation of [Sm(DippForm)2(thf)2] with Hg(C[triple chemical bond]CPh)2, respectively. The monomeric, six-coordinate, cisoid [Ln(DippForm)2(C[triple chemical bond]CPh)(thf)] complexes have trigonal prismatic geometries and rare (for Ln) terminal C[triple chemical bond]CPh groups with contrasting Ln--C[triple chemical bond]C angles (Ln=Nd, 170.9(4) degrees; Ln=Sm, 142.9(7) degrees). Their formation lends support to the view that [Ln(DippForm)2F(thf)] complexes arise from oxidative formation and C--F activation of [Ln(DippForm)2(C6F5)] intermediates. 相似文献
145.
Zuniga MF Deacon GB Ruhlandt-Senge K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(7):1921-1928
The preparation of heterobimetallic complexes consisting of alkali and heavy alkaline earth metals remains a challenge due to limited available synthetic strategies. Here we present a new class of group 1, Ba compounds of the type [M(n){Ba(Odpp)(2+n)}] (M=Na(n=1) (1), K(n=1) (2), Cs(n=1) (3), Li(n=2) (4); HOdpp=2,6-diphenylphenol) and the Lewis base adducts [Li(2)(thf)(2){Ba(Odpp)(4)}]PhMe (5) and [K{Ba(Odpp)(3)(diglyme)}] (6) (diglyme=[bis(2-methoxy)ethyl ether]) as the first representatives of heterobimetallic group 1, Ba species of low nuclearity. The compounds display a significant degree of metal-arene interaction, believed to be a key factor in stabilizing these highly reactive species. Obtained by solid-state direct metalation, the target compounds are available without further work-up. 相似文献
146.
A series of novel heterobimetallic group 1/strontium and group 1/calcium aryloxo complexes having the composition [MAe(Odpp)3] [Ae=Sr and M=Na (1), K (2, 3), Cs (4); Ae=Ca and M=Na (5), K (6), Cs (7)] or [M2Ae(Odpp)4] [M=Li and Ae=Sr (9), Ca (10)] have been prepared using 2,6-diphenylphenol (HOdpp) as the ligand. Through the use of solid-state direct metalation, these compounds were obtained either directly from the reaction vessel or after workup in toluene. The Lewis base adduct [KCa(Odpp)3(thf)] (8) was obtained by treatment of [KCa(Odpp)3] (6) with tetrahydrofuran (thf). All of the compounds displayed extensive metal-pi-arene interactions, which provide significant stabilization in these reactive species. The thermal stabilities and volatilities of representative heterobimetallic strontium and calcium complexes were investigated using thermogravimetric analysis. 相似文献
147.
Samar Beaini Glen B. Deacon Craig M. Forsyth Peter C. Junk Prof. 《无机化学与普通化学杂志》2008,634(15):2903-2906
The complex [Yb(Ph2pz)3(LiOBu)]2 ( 1 ) (Ph2pz = 3,5‐diphenylpyrazolate), fortuitously obtained from reaction of Yb metal with a lithium containing sample of [SnMe3(Ph2pz)] at elevated temperatures forms a centrosymmetric butoxy‐ and pyrazolate‐bridged open box structure. Each ytterbium atom is eight coordinate with one chelating Ph2pz ligand, one μ‐η2:η2 bridging pyrazolate, one μ‐η2(Yb):η4(Li) Ph2pz group and two bridging butoxide ligands. Each lithium atom is unsymmetrically chelated by an η2‐Ph2pz group, η4(N,C(pz)C2(Ph)) bonded by another pyazolate group, and bridged through a butoxide oxygen atom to two ytterbium atoms. The type of η4‐pyrazolate coordination is unprecedented and is the first observation of interactions to a metal by the Ph rings of the Ph2pz ligand. The complex [Li(dme)3][Eu(Ph2pz)3(dme)] ( 2 ) obtained from reaction of Eu metal with the same sample of [SnMe3(Ph2pz)] in dme at room temperature is a charged separated species with the first anionic pyrazolatolanthanoidate(II) complex in which europium is eight coordinate with three chelating Ph2pz ligands and a chelating dme. 相似文献
148.
Glen B. Deacon Penny R. Drago Dirk Gbbels Mathias S. Wickleder Gerd Meyer 《无机化学与普通化学杂志》2001,627(5):811-813
From the reaction of PtCl2(hex) (hex = hexa‐1,5‐diene) with LiC6F5 in diethyl ether, the complex [Pt{CH(CH2C6F5)CH2CH2CH=CH2}(C6F5)(OH2)] ( 1 ) was isolated. The crystal structure (monoclinic, C2/c (no. 15), Z = 8, a = 15.241(3), b = 16.579(2), c = 16.225(2) Å, β = 111.12(2)°) shows a complex with square planar coordination around platinum with a template formed 1‐pentafluorophenylhex‐5‐en‐2‐yl ligand, and C6F5 and aqua ligands trans to the double bond and alkyl carbon, respectively. 相似文献
149.
150.
Engineering of efficient panchromatic sensitizers for nanocrystalline TiO(2)-based solar cells. 总被引:20,自引:0,他引:20
M K Nazeeruddin P Péchy T Renouard S M Zakeeruddin R Humphry-Baker P Comte P Liska L Cevey E Costa V Shklover L Spiccia G B Deacon C A Bignozzi M Gr?tzel 《Journal of the American Chemical Society》2001,123(8):1613-1624
A new series of panchromatic ruthenium(II) sensitizers derived from carboxylated terpyridyl complexes of tris-thiocyanato Ru(II) have been developed. Black dye containing different degrees of protonation [(C(2)H(5))(3)NH][Ru(H(3)tcterpy)(NCS)(3)] 1, [(C(4)H(9))(4)N](2)[Ru(H(2)tcterpy)(NCS)(3)] 2, [(C(4)H(9))(4)N](3)[Ru(Htcterpy)(NCS)(3)] 3, and [(C(4)H(9))(4)N](4)[Ru(tcterpy)(NCS)(3)] 4 (tcterpy = 4,4',4' '-tricarboxy-2,2':6',2' '-terpyridine) have been synthesized and fully characterized by UV-vis, emission, IR, Raman, NMR, cyclic voltammetry, and X-ray diffraction studies. The crystal structure of complex 2 confirms the presence of a Ru(II)N6 central core derived from the terpyridine ligand and three N-bonded thiocyanates. Intermolecular H-bonding between carboxylates on neighboring terpyridines gives rise to 2-D H-bonded arrays. The absorption and emission maxima of the black dye show a bathochromic shift with decreasing pH and exhibit pH-dependent excited-state lifetimes. The red-shift of the emission maxima is due to better pi-acceptor properties of the acid form that lowers the energy of the CT excited state. The low-energy metal-to-ligand charge-transfer absorption band showed marked solvatochromism due to the presence of thiocyanate ligands. The Ru(II)/(III) oxidation potential of the black dye and the ligand-based reduction potential shifted cathodically with decreasing number of protons and showed more reversible character. The adsorption of complex 3 from methoxyacetonitrile solution onto transparent TiO(2) films was interpreted by a Langmuir isotherm yielding an adsorption equilibrium constant, K(ads), of (1.0 +/- 0.3) x 10(5) M(-1). The amount of dye adsorbed at monolayer saturation was (n(alpha) = 6.9 +/- 0.3) x 10(-)(8) mol/mg of TiO(2), which is around 30% less than that of the cis-di(thiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylate)ruthenium(II) complex. The black dye, when anchored to nanocrystalline TiO(2) films achieves very efficient sensitization over the whole visible range extending into the near-IR region up to 920 nm, yielding over 80% incident photon-to-current efficiencies (IPCE). Solar cells containing the black dye were subjected to analysis by a photovoltaic calibration laboratory (NREL, U.S.A.) to determine their solar-to-electric conversion efficiency under standard AM 1.5 sunlight. A short circuit photocurrent density obtained was 20.5 mA/cm(2), and the open circuit voltage was 0.72 V corresponding to an overall conversion efficiency of 10.4%. 相似文献