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1.
Jonathan S. B. Park Paul M. Wood Michael J. Davies Bruce C. Gilbert Adrian C. Whitwood 《Free radical research》1997,27(5):447-458
The reaction of FeII oxalate with hydrogen peroxide and dioxygen was studed for oxalate concentrations up to 20 mM and pH 2-5, under which conditions mono- and bis-oxalate comlexes (FeII(ox) and FeII(ox)22-) and uncomplexed Fe2+ must be considered. The reaction of FeII oxalate with hydrogen peroxide (Fe2+ + H2O2 → Fe3+ + *OH + OH-) was monitored in continuous flow by ESR with t-butanol as a radical trap. The reaction is much faster than for uncomplexed Fe2+ and a rate constant, k = 1 × 104 M-1 s-1 is deduced for FeII(ox). The reaction of FeII oxalate with dioxygen is strongly pH dependent in a manner which indicates that the reactive species is FeII(ox)22-, for which an apparent second order rate constant, k = 3.6 M-1 s-1, is deduced. Taken together, these results provide a mechanism for hydroxyl radical production in aqueous systems containing FeII complexed by oxalate. Further ESR studies with DMPO as spin trap reveal that reaction of FeII oxalate with hydrogen peroxide can also lead to formation of the carboxylate radical anion (CO2*-), an assignment confirmed by photolysis of FeIII oxalate in the presence of DMPO. 相似文献
2.
The positive ion electrospray mass spectrometry (ESI-MS) of trans-[Ru(NO)Cl)(dpaH)2]Cl2 (dpaH=2,2′-dipyridylamine), obtained from the carrier solvent of H2O–CH3OH (50:50), revealed 1+ ions of the formulas [RuII(NO+)Cl(dpaH)(dpa)]+ (m/z=508), [RuIIICl(dpaH)(dpa−)]+ (m/z=478), [RuII(NO+)(dpa)2]+ (m/z=472), [RuIII(dpa)2]+ (m/z=442), originating from proton dissociation from the parent [RuII(NO+)Cl(dpaH)2]2+ ion with subsequent loss of NO (17.4% of dissociative events) or loss of HCl (82.6% of dissociative events). Further loss of NO from the m/z=472 fragment yields the m/z=442 fragment. Thus, ionization of the NH moiety of dpaH is a significant factor in controlling the net ionic charge in the gas phase, and allowing preferential dissociation of HCl in the fragmentation processes. With NaCl added, an ion pair, {Na[RuII(NO)Cl(dpa)2]}+ (m/z=530; 532), is detectable. All these positive mass peaks that contain Ru carry a signature ‘handprint’ of adjacent m/z peaks due to the isotopic distribution of 104Ru, 102Ru, 101Ru, 99Ru, 98Ru and 96Ru mass centered around 101Ru for each fragment, and have been matched to the theoretical isotopic distribution for each set of peaks centered on the main isotope peak. When the starting complex is allowed to undergo aquation for two weeks in H2O, loss of the axial Cl− is shown by the approximately 77% attenuation of the [RuII(NO+)Cl(dpaH)(dpa)]+ ion, being replaced by the [RuII(NO+)(H2O)(dpa)2]+ (m/z=490) as the most abundant high-mass species. Loss of H2O is observed to form [RuII(NO+)(dpa)2]+ (m/z=472). No positive ion mass spectral peaks were observed for RuCl3(NO)(H2O)2, ‘caged NO’. Negative ions were observed by proton dissociation forming [RuII(NO)Cl3(H2O)(OH)]− in the ionization chamber, detecting the parent 1− ion at m/z=274, followed by the loss of NO as the main dissociative pathway that produces [RuIIICl3(H2O)(OH)]− (m/z=244). This species undergoes reductive elimination of a chlorine atom, forming [RuIICl2(H2O)(OH)]− (m/z=208). The ease of the NO dissociation is increased for the negative ions, which should be more able to stabilize a RuIII product upon NO loss. 相似文献
3.
The molecular structure of the title complexes [Fe(H2O)4][Fe(Hedta)(H2O)]2 · 4H2O (I) and [Fe(H[2edta)(H2O)] · 2H2O (II) have been determined by single-crystal X-ray analyses. The crystal data are as follows: I: monoclinic, P21/n, A = 11.794(2), B = 15.990(2), C = 9.206(2) Å, β = 90.33(1)°, V = 1736.1(5) Å3, Z = 2 and R = 0.030; II: monoclinic, C2/c, A = 11.074(2), B = 9.856(2), C = 14.399(2) Å, β = 95.86(1)°, V = 1563.3(4) Å3, Z = 4 and R = 0.025. I is found to be isomorphous with the MnII analog reported earlier and to contain a seven-coordinate and approximately pentagonal-bipyramidal (PB) [FeII(Hedta)(H2O]− unit in which Hedta acts as a hexadentate ligand. The [FeII(H2edta)(H2O)] unit in II has also a seven-coordinate PB structure with the two protonated equatorial glycine arms both remaining coordinated, and thus bears a structural resemblance to the seven-coordinate [CoII(H2edta)(H2O)] reported previously. 相似文献
4.
With exposure to trace amounts of air and moisture, the Cr2(II, II) complex Cr2(μ-3,5Cl2-form)4, where 3,5Cl2-form is [(3,5-Cl2C6H3)NC(H)N(3,5-Cl2C6H3)−], undergoes an oxidative addition reaction. Structural information from the X-ray crystal structure of the edge-sharing bioctahedral (ESBO) Cr2(III, III) product Cr2(μ-OH)2(μ-3,5Cl2-form)2(η2-3,5Cl2-form)2 (1) indicates 1 has a significantly longer Cr–Cr distance [2.732(2) Å] than Cr2(μ-3,5Cl2-form)4 [1.9162(10) Å], but the shortest Cr–Cr distance in an ESBO Cr2(III, III) complex recorded to date. 相似文献
5.
The complex [Ru(SB12H11)(NH3)5]·2H2O has been prepared by the reaction of Cs2B12H11SH with [RuCl(NH3)5]Cl2 in aqueous solution. The complex represents the first reported example of the borocaptate anion acting as a ligand. The structure of the complex has been determined by single crystal X-ray diffraction analysis. The crystal parameters are monoclinic, space group P21/c, A = 8.056(1), B = 14.240(2), C = 15.172(2) Å, β=98.48° and Z = 4. The ruthenium atom has a distorted octahedral coordination. The distortion is probably due to the high (3−) charge and the large bulk of the borocaptate ligand. These features can also be observed in the spectroscopic properties of the complex. 相似文献
6.
New mixed metal complexes SrCu2(O2CR)3(bdmap)3 (R = CF3 (1a), CH3 (1b)) and a new dinuclear bismuth complex Bi2(O2CCH3)4(bdmap)2(H2O) (2) have been synthesized. Their crystal structures have been determined by single-crystal X-ray diffraction analyses. Thermal decomposition behaviors of these complexes have been examined by TGA and X-ray powder diffraction analyses. While compound 1a decomposes to SrF2 and CuO at about 380°C, compound 1b decomposes to the corresponding oxides above 800°C. Compound 2 decomposes cleanly to Bi2O3 at 330°C. The magnetism of 1a was examined by the measurement of susceptibility from 5–300 K. Theoretical fitting for the susceptibility data revealed that 1a is an antiferromagnetically coupled system with g = 2.012(7), −2J = 34.0(8) cm−1. Crystal data for 1a: C27H51N6O9F9Cu2Sr/THF, monoclinic space group P21/m, A = 10.708(6), B = 15.20(1), C = 15.404(7) Å, β = 107.94(4)°, V = 2386(2) Å3, Z = 2; for 1b: C27H60N6O9Cu2Sr/THF, orthorhombic space group Pbcn, A = 19.164(9), B = 26.829(8), C = 17.240(9) Å, V = 8864(5) Å3, Z = 8; for 2: C22H48O11N4Bi2, monoclinic space group P21/c, A = 17.614(9), B = 10.741(3), C = 18.910(7) Å, β = 109.99(3)°, V = 3362(2) Å3, Z = 4. 相似文献
7.
The reaction of ReH92− with Mo(diglyme)(CO)3 leads to the formation of the mixed metal cluster trianion, ReMo3H4(CO)123−. This species has been characterized analytically, spectroscopically and through X-ray diffraction analysis. A pseudo-tetrahedral arrangement of M(CO)3 fragments is adopted, such that each set of three carbonyl ligands eclipses the adjacent three tetrahedral edges, an apparent result of the location of the hydride ligands on the tetrahedral faces. Variable temperature NMR studies revealed a fluctional process for some of the carbonyl ligands, but not for the hydrides. Crystal data for [Me4N]3[ReMo3H4(CO)12]·THF; space group P21/n, a = 12.157(2), B = 21.480(4), C = 15.964(3) Å, β = 98.26(1)°, Z = 4, R = 0.067 and Rw = 0.076. 相似文献
8.
Anna Bonamartini Corradi Maria Rita Cramarossa Monica Saladini Luigi Pietro Battaglia Jolanda Giusti 《Inorganica chimica acta》1995,230(1-2):59-65
The chlorocadmate(II) systems of (H2me2pipz)[Cd2Cl6(H2O)2] (1) and (H2mepipz)2[Cd3Cl10(H2O)] (2) (L = me2pipz = N,N′-dimethylpiperazine; L′ = mepipz = N-methylpiperazine) were prepared and their structural and thermal properties investigated. Compound 1 is monoclinic, space group P21/c, A = 7.664(1), B = 7.472(4), C = 15.347(1) Å, β = 99.468(7)°, Z = 2, R = 0.024. The crystal structure consists of organic cations and infinite one-dimensional chains of [CdCl3(H2O)]n3− anions. Each Cd atom is octahedrally surrounded by bridged and terminal chlorine atoms and by a water molecule, which is in trans position with respect to the terminal chlorine atom. Inter- and intrachain hydrogen bond interactions between the terminal chlorine atoms and the water molecules contribute to the crystal packing. Compound 2 is orthorhombic, space group Cmc21, A = 15.286(3), B = 13.354(3), C = 13.154(3) Å, R = 0.023. The crystal structure consists of organic dications and infinite chains of [Cd2Cl6(CdCl4H2O]n4− units running along the [001] axis. Each unit is formed of regularly alternate six-coordinated Cd atoms, one of them linking one pentacoordinated Cd atom which completes its coordination througha water molecule. A strong hydrogen bond interaction involving the organic dication and the inorganic chain contributes to the crystal packing. Differential hydrogen bond interaction involving the organic dication and the inorganic chain contributes to the crystal packing. Differential scanning calorimetry measurements did not show the presence of any structural phase transitions. The structures are compared with those of (H2pipz)[Cd2Cl6(H2O)2] (3), (H2mepipz)[Cd2Cl6(H2O)2]·H2O (4) and (H2mepipz)[Cd2Cl6] (5) (L = pipz = piperazine, L′ = mepipz = N-ethylpiperazine). 相似文献
9.
Konstantinos D. Demadis Mohammed Bakir Bert G. Klesczewski Darryl S. Williams Peter S. White Thomas J. Meyer 《Inorganica chimica acta》1998,270(1-2):511-526
Rapid reactions occur between [OsVI(tpy)(Cl)2(N)]X (X = PF6−, Cl−, tpy = 2,2′:6′,2″-terpyridine) and aryl or alkyl phosphi nes (PPh3, PPh2Me, PPhMe2, PMe3 and PEt3) in CH2Cl2 or CH3CN to give [OsIV(tpy)(Cl)2(NPPh3)]+ and its analogs. The reaction between trans-[OsVI(tpy)(Cl)2(N)]+ and PPh3 in CH3CN occurs with a 1:1 stoichiometry and a rate law first order in both PPh3 and OsVI with k(CH3CN, 25°C) = 1.36 ± 0.08 × 104 M− s−1. The products are best formulated as paramagnetic d4 phosphoraniminato complexes of OsIV based on a room temperature magnetic moment of 1.8 μB for trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6), contact shifted 1H NMR spectra and UV-Vis and near-IR spectra. In the crystal structures of trans-[OsIV(tpy)(Cl)2( NPPh3)](PF6)·CH3CN (monoclinic, P21/n with a = 13.384(5) Å, b = 15.222(7) Å, c = 17.717(6) Å, β = 103.10(3)°, V = 3516(2) Å3, Z = 4, Rw = 3.40, Rw = 3.50) and cis-[OsIV(tpy)(Cl)2(NPPh2Me)]-(PF6)·CH3CN (monoclinic, P21/c, with a = 10.6348(2) Å, b = 15.146(9) ÅA, c = 20.876(6) Å, β = 97.47(1)°, V = 3334(2) Å3, Z = 4, R = 4.00, Rw = 4.90), the long Os-N(P) bond lengths (2.093(5) and 2.061(6) Å), acute Os-N-P angles (132.4(3) and 132.2(4)°), and absence of a significant structural trans effect rule out significant Os-N multiple bonding. From cyclic voltammetric measurements, chemically reversible OsV/IV and OsIV/III couples occur for trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6) in CH3CN at +0.92 V (OsV/IV) and −0.27 V (OsIV/III) versus SSCE. Chemical or electrochemical reduction of trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6) gives isolable trans-OsIII(tpy)(Cl)2(NPPh3). One-electron oxidation to OsV followed by intermolecular disproportionation and PPh3 group transfer gives [OsVI(tpy)Cl2(N)]+, [OSIII(tpy)(Cl)2(CH3CN)]+ and [Ph3=N=PPh3]+ (PPN+). trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6) undergoes reaction with a second phosphine under reflux to give PPN+ derivatives and OsII(tpy)(Cl)2(CH3CN) in CH3CN or OsII(tpy)(Cl)2(PR3) in CH2Cl2. This demonstrates that the OsVI nitrido complex can undergo a net four-electron change by a combination of atom and group transfers. 相似文献
10.
Metathesis of [(η3:η3−C10H16)Ru(Cl) (μ−Cl)]2 (1) with [R3P) (Cl)M(μ-Cl)]2 (M = Pd, Pt), [Me2NCH2C6H4Pd(μ-Cl)]2 and [(OC)2Rh(μ-Cl)]2 affords the heterobimetallic chloro bridged complexes (η3:η3-C10H16) (Cl)Ru(μ-Cl)2M(PR3)(Cl) (M = Pd, Pt), (η3:η3-C10H16) (Cl)Ru(μ-Cl)2PdC6H4CH2NMe2 and (η3:η3-C10H16) (Cl)Ru(μ-Cl)2Rh(CO)2, respectively. Complex 1 reacts with [Cp*M(Cl) (μ-Cl)]2 (M = Rh, Ir), [p-cymene Ru(Cl) (μ-Cl]2 and [(Cy3P)Cu(μ-Cl)]2 to give an equilibrium of the heterobimetallic complexes and of educts. The structures of (η3:η3-C10H16)Ru(μ-Cl)2Pd(PR3) (Cl) (R = Et, Bu) and of one diastereoisomer of (η3:η3-C10H16)Ru(μ-Cl)2IrCp*(Cl) were determined by X-ray diffraction. 相似文献
11.
M. Tsaramyrsi D. Kavousanaki C. P. Raptopoulou A. Terzis A. Salifoglou 《Inorganica chimica acta》2001,320(1-2):47-59
The aqueous chemistry of vanadium with physiologically relevant ligands constitutes a subject of burgeoning research, extending from bacterial metalloenzymic functions to human-health physiology. Vanadium, in the form of VCl3 and V2O5, reacted expediently with citric acid, in a 1:2 molar ratio in water at pH4, and, in the presence of various cations, afforded crystalline materials bearing the general formula (Cat)2[V2O4(C6H6O7)2]·nH2O (A) (Cat+=Na+, NH4 +, n=2; Me4N+, K+, n=4). Exploration of the reactivity of A toward H2O2 yielded the peroxo-containing complexes (Cat)2[V2O2(O2)2(C6H6O7)2]·2H2O (B) (Cat+=K+, NH4 +). Both classes of compounds were characterized analytically and spectroscopically. The X-ray structures of complexes A and B emphasize the exceptional stability of the dimeric rhombic unit VV 2O2, which is retained upon H2O2 reaction, and the preserved mode of coordination of the citrate ligand as a doubly deprotonated moiety. In these complexes, typical six and eight coordination numbers were observed for the Na+ and K+ counter-ions, respectively. The variety of synthetic approaches leading to A, along with the stepwise and direct assembly and isolation of peroxo-compounds (B), denotes the significance of reaction pathways and intermediates in vanadium(III–V)–citrate synthetic chemistry. Hence, a systematic investigation of reactivity modes in aqueous vanadium–citrate systems emerges as a crucial tool for the establishment of chemical interconnectivity among low MW complex species, potentially participating in the intricate biodistribution of that metal ion in biological fluids. 相似文献
12.
Rates of stepwise anation of cis-Cr(ox)2(H2O2)− with SCN−/N3−, Cr(acac)2(H2O)2+ with SCN− and Cr(atda)(H2O)2 with SCN− have been investigated in weakly acidic aqueous solutions. Rate constants, kI and kII for the two steps in each system, are composite as kx = kx0+kxX[X−] (x = I, II; X− = SCN−, N3−). These rate constants have been evaluated also as the corresponding ΔH≠ and ΔS≠ values. The results obtained and the plausible Id mechanism seem to suggest Cr---OOC bond dissociation (hence a strongly negative ΔS≠) generating the transition state in each system with outer-sphere association forming the precursor complex in the X− dependent paths. 相似文献
13.
[Fe(TIM)(CH3CN)2](PF6)2 (1) (TIM = 2,3,9,10-tetramethyl-1,4,8,11-tetraazacyclodeca-1,3,8,10-tetraene) forms a complex with NO reversibly in CH3CN (53±1% converted to the NO complex) or 60% CH3OH/40% CH3CN (81±1% conversion). Quantitative NO complexation occurs in H2O or CH3OH solvents. The EPR spectrum of [Fe(TIM)(solvent)NO]2+ in frozen 60/40 CH3OH/CH3CN at 77 K shows a three line feature at g=2.01, 1.99 and 1.97 of an S=1/2FeNO7 ground state. The middle line exhibits a three-line N-shf coupling of 24 G indicating a six-coordinate complex with either CH3OH or CH3CN as a ligand trans to NO. In H2O [Fe(TIM)(H2O)2]2+ undergoes a slow decomposition, liberating 2,3-butanedione, as detected by 1H NMR in D2O, unless a π-acceptor axial ligand, L=CO, CH3CN or NO is present. An equilibrium of 1 in water containing CH3CN forms [Fe(TIM)(CH3CN)(H2O)]2+ which has a formation constant KCH3CN=320 M−1. In water KNOKCH3CN since NO completely displaces CH3CN. [Fe(TIM)(CH3CN)2]2+ binds either CO or NO in CH3CN with KNO/KCO=0.46, sigificantly lower than the ratio for [FeII(hemes)] of 1100 in various media. A steric influence due to bumping of β-CH2 protons of the TIM macrocycle with a bent S=1/2 nitrosyl as opposed to much lessened steric factors for the linear Fe---CO unit is proposed to explain the lower KNO/KCO ratio for the [Fe(TIM)(CH3CN)]2+ adducts of NO or CO. Estimates for formation constants with [Fe(TIM)]2+ in CH3CN of KNO=80.1 M−1 and KCO=173 M− are much lower than to hemoglobin (where KNO=2.5×1010 M−1 and KCO=2.3×107) due to a reversal of steric factors and stronger π-backdonation from [FeII(heme)] than from [FeII(TIM)(CH3CN)]2+. 相似文献
14.
Oleg V. Gusev Mikhail A. Ievlev Konstantin A. Lyssenko Pavel V. Petrovskii Nikolai A. Ustynyuk Peter M. Maitlis 《Inorganica chimica acta》1998,280(1-2):249-256
The reaction of RuCl3(H2O), with C5Me4CF3J in refluxing EtOH gives [Ru2(η5-C5Me1CF2)2 (μ-Cl2] (20 in 44% yield. Dimer 2 antiferromagnetic (−2J=200 cm1). The crystal structures of 2 (rhombohedral system, R3 space group, Z=9, R=0.0589) and [Rh2(η5-C5Me4CF3(2Cl2(μ-Cl)2] (3) (rhombohedral system.
space group, Z = 9, R = 0.0641) were solved; both complexes have dimeric structures with a trans arrangement of the η5-C5Me4CF4 rings. Comparison of the geometry of 2 and 3 with those of the corresponding η5-C5Me5 complexes shows that lowering the ring symmetry causes significant distortion of the M2(μ-Cl)2 moiety. The analysis of the MCl3 fragment conformations in 2 and 3 and in the η5-C5ME5 analogues shows that they are correlated with the M---M distances. The Cl atoms are displaced by Br on reaction of 2 with KBr in MeOH to give the diamagnetic dimer [Ru2(η5-C5Me4CF3)2Br2 (μ-Br2] (4). Complex 2 reacts with O2 in CH2Cl2 solution at ambient temperature to form a mixture of isomeric η6-fulvene dimers [Ru2(η6-C5Me3CF3 = CH2)2Cl2(μ-Cl)2] (5). Reactions of 5 with CO and allyl chloride give Ru(η5-C5Me3CF3CH2Cl)(CO)2Cl (6) and Ru(η5-C5Me3CF3CF3CH2Cl)(η3-C3H5)Cl2 (7) respectively. 相似文献
15.
Ademir Neves Karl Wieghardt Bernhard Nuber Johannes Weiss 《Inorganica chimica acta》1988,150(2):183-187
The reaction of N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (tpen) with VCl3 in CH3CN yields Cl3V(tpen)VCl3 which was hydrolyzed in water in the presence of oxygen affording [V2O2(μ-OH)2(tpen)]I2·2H2O, the crystal structure of which has been determined. Asyn-{OV(μ-OH)2VO}2+ core has been identified where the V(IV) centers are antiferromagnetically coupled (J = −150 cm−1;g = 1.80). 相似文献
16.
Reaction of LaCl3·7H2O containing small amounts of La(NO3)3·7H2O as an impurity with 12-crown-4 or 18-crown-6 in 3:1 CH3CN:CH3OH resulted in the isolation of the mixed anion complexes [LaCl2(NO3)(12-crown-4)]2, [La(NO3)(OH2)4(12-crown-4)]Cl2·CH3CN and [LaCl2(NO3)(18-crown-6)]. The nine-coordinate dimer, [LaCl2(NO3)(12-crown-4)]2, has all of the anions in the inner coordination sphere and La3+ has a capped square antiprismatic geometry. It crystallizes in the orthorhombic space group Pbca with (at −150 °C) a = 12.938(6), B = 15.704(3), C = 13.962(2) Å, and Dcalc = 2.08 g cm−3 for Z = 4. The second complex isolated from the same reaction, [La(NO3)(OH2)4(12-crown-4)]Cl2·CH3CN, has the bidentate nitrate anion in the inner coordination sphere but the two chloride anions are in a hydrogen bonded outer sphere. This complex is ten-coordinate 4A,6B-expanded dodecahedral and crystallizes in the monoclinic space group P21 with (at 20 °C) A = 7.651(2), B = 11.704(7), C = 11.608(4) Å, β = 95.11(2)°, and Dcalc = 1.80 g cm−3 for Z = 2. The 18-crown-6 complex, [LaCl2(NO3)(18-crown-6)], has all inner sphere anions and has ten-coordinate 4A,6B-expanded dodecahedral La3+ centers. It crystallizes in the orthorhombic space group Pbca with (at 20 °C) a = 14.122(7), B = 13.563(5), C = 19.311(9) Å, and Dcalc = 1.89 g cm−3 for Z = 8. 相似文献
17.
Tania De Simone Ron S. Dickson Brian W. Skelton Allan H. White 《Inorganica chimica acta》1995,240(1-2):323-333
The phosphinoalkenes Ph2P(CH2)nCH=CH2 (n= 1, 2, 3) and phosphinoalkynes Ph2P(CH2)n C≡CR (R = H, N = 2, 3; R = CH3, N = 1) have been prepared and reacted with the dirhodium complex (η−C5H5)2Rh2(μ−CO) (μ−η2−CF3C2CF3). Six new complexes of the type (ν−C5H5)2(Rh2(CO) (μ−η1:η1−CF3C2CF3)L, where L is a P-coordinated phosphinoalkene, or phosphinoalkyne have been isolated and fully characterized; the carbonyl and phosphine ligands are predominantly trans on the Rh---Rh bond, but there is spectroscopic evidence that a small amount of the cis-isomer is formed also. Treatment of the dirhodium-phosphinoalkene complexes with (η−CH3C5H4)Mn(CO)2thf resulted in coordination of the manganese to the alkene function. The Rh2---Mn complex [(η−C5H5)2Rh2(CO) (μ−η1:η1−CF3C2CF3) {Ph2P(CH2)3CH=CH2} (η−CH3C5H4)Mn(CO)2] was fully characterized. Simi treatment of the dirhodium-phosphinoalkyne complexes with Co2(CO)8 resulted in the coordination of Co2(CO)6 to the alkyne function. The Rh2---Co2 complex [(η−C5H5)2Rh2(CO) (μ−η1:η1−CF3C2CF3) {Ph2PCH2C≡CCH3}Co2(CO)2], C37H25Co2F6O7PRh2, was fully characteriz spectroscopically, and the molecular structure of this complex was determined by a single crystal X-ray diffraction study. It is triclinic, space group
(Ci1, No. 2) with a = 18.454(6), B = 11.418(3), C = 10.124(3) Å, = 112.16(2), β = 102.34(3), γ = 91.62(3)°, Z = 2. Conventional R on |F| was 0.052 fo observed (I > 3σ(I)) reflections. The Rh2 and Co2 parts of the molecule are distinct, the carbonyl and phosphine are mutually trans on the Rh---Rh bond, and the orientations of the alkynes are parallel for Rh2 and perpendicular for Co2. Attempts to induce Rh2Co2 cluster formation were unsuccessful. 相似文献
18.
Mongelli MT Heinecke J Mayfield S Okyere B Winkel BS Brewer KJ 《Journal of inorganic biochemistry》2006,100(12):1983-1987
The complexes [(bpy)2Ru(dpp)]Cl2, [(phen)2Ru(dpp)]Cl2, and [(Ph2phen)2Ru(dpp)]Cl2 (where dpp = 2,3-bis(2-pyridyl)pyrazine, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, Ph2phen = 4,7-diphenyl-1,10-phenanthroline) have been investigated and found to photocleave DNA via an oxygen-mediated pathway. These light absorbing complexes possess intense metal-to-ligand charge transfer (MLCT) transitions in the visible region of the spectrum. The [(TL)2Ru(dpp)]2+ systems populate 3MLCT states after visible light excitation, giving rise to emissions in aqueous solution centered at 692, 690, and 698 nm for TL = bpy, phen, and Ph2phen respectively. The 3MLCT states and emissions are quenched by O2, producing a reactive oxygen species. These complexes photocleave DNA with varying efficiencies, [(Ph2phen)2Ru(dpp)]2+ > [(phen)2Ru(dpp)]2+ > [(bpy)2Ru(dpp)]2+. The presence of the polyazine bridging ligand will allow these chromophores to be incorporated into larger supramolecular assemblies. 相似文献
19.
New tin and thallium reagents capable of transferring the 1,2-di-tert-butylcyclopentadienyl moiety are easily prepared and utilized in furthering the transition metal organometallic chemistry of this intersting ligand. Lithium 1,2-di-tert-butylcyclopentadienide (1) reacts cleanly and selectively with SnClMe3 to give 2,3-di-tert-butyl-5-trimethylstannyl-1,3-cyclopentadiene (2), which in turn reacts with Re(CO)5Br to form the half-sandwich complex [Re(η5-C5H3(1,2-But)2)(CO)3] (3). The reaction between thallium ethoxide and 1,5-ditert-butyl-1,3-cyclopentadiene in hexane affords the excellent cyclopentadienyl transfer reagent, thallium 1,2-di-tert-butylcyclopentadienide (4). The thallium salt reacts with [Ru(COD)Cl2]n to give the sandwich complex [Ru(η5-C5H3(1,2-Bu2t)2)] (5). 相似文献
20.
William B. Connick Angel J. Di Bilio Michael G. Hill Jay R. Winkler Harry B.Gray 《Inorganica chimica acta》1995,240(1-2):169-173
The structure of [Re(CO)3(phen)(im)]2SO4·4H2O has been determined by X-ray crystallography. The yellow crystals are orthorhombic, space group Pccn (No. 56), with a=17.456(6), B=18.194(5), C=12.646(4) Å, R=0.063 for Fo2>0, R=0.032 for Fo2>3σ. The compound, which also has been characterized by IR, 1H NMR, and UV---Vis spectroscopies, exhibits room temperature luminescence in aqueous solution (τ=120 ns) as well as reversible oxidation and reduction in acetonitrile solution (1.85 and −1.30 V versus SCE). The redox properties of the excited state of the complex (E0(Re+*/0 = 1.2; E0(Re2+/+*) = −0.7 V) are being exploited in studies of laser-induced electron tunneling in Re(CO)3(phen)(histidine)-modified proteins. 相似文献