- Efficient Access to 5-Bromo- and 5,6-Dibromophenanthroline Ligands
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Bromo-functionalized precursor molecules are essential for generating desired target compounds through cross-coupling reactions. Herein we show an improved synthetic route, feasible at low temperatures and affording high yields, to the ligands 5-bromo-1,10-phenanthroline (1) and 5,6-dibromo-1,10-phenanthroline (2). The corresponding ruthenium complexes, containing various equivalents of ligand 2, are easily accessible in high yields, including the analogue of tris-homoleptic [Ru(bpy)3]2+ (bpy = 2,2′-bipyridine), [Ru(2)3]2+. X-ray diffraction analyses have provided detailed information on the structures of the ligands and their corresponding metal complexes. An investigation of the electrochemical properties has provided detailed information on the 3MLCT state localized on 2. We show the conversion of heteroleptic ruthenium complexes of these ligands in Suzuki cross-coupling reactions whereas the ligands did not undergo reaction under the same conditions.
- Stumper, Anne,Pilz, Thomas David,Schaub, Markus,G?rls, Helmar,Sorsche, Dieter,Peuntinger, Katrin,Guldi, Dirk,Rau, Sven
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- Synthesis of poly(1,10-phenanthroline-5,6-diyl)s having a π-stacked, helical conformation
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5,6-Dibromo-1,10-phenanthroline and 2,9-di-n-butyl-5,6-dibromo-1,10-phenanthroline were polymerized using a Ni catalyst to afford helical polymers in which the phenanthroline moieties are densely stacked on top of each other. Polymerization of the latter monomer using a chiral catalyst led to a preferred-handed helix. This is the first Ni-catalyzed helix-sense-selective polymerization of aromatic compounds.
- Yang, Weixi,Nakano, Tamaki
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- Synthesis, Characterization and Photobiological Studies of Ru(II) Dyads Derived from α-Oligothiophene Derivatives of 1,10-Phenanthroline
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Three new bis(2,2′-bipyridine)-heteroleptic Ru(II) dyads incorporating thienyl groups (n?=?1–3, compounds 1, 2 and 3, respectively) appended to 1,10-phenanthroline were synthesized and characterized to investigate the impact of n on the photophysical and photobiological properties within the series. All three complexes showed unstructured emission near 618?nm from a triplet metal-to-ligand charge transfer (3MLCT) state with a lifetime (τem) of approximately 1?μs. Transient absorption measurements revealed an additional excited state that was nonemissive and long-lived (τTA?=?43?μs for 2 and 27?μs for 3), assigned as a triplet intraligand (3IL) state that was accessible only in 2 and 3. All three complexes were strong singlet oxygen (1O2) sensitizers, with quantum yields (Φ?) for 2 and 3 being the largest (74–78%), and all three were photocytotoxic to cancer cells with visible light activation in the order: 3?>?2?>?1. Cell-free DNA photodamage followed the same trend, where potency increased with decreasing 3IL energy. Compounds 2 and 3 also showed in?vitro photobiological effects with red light (625?nm), where their molar absorptivities were ?1?cm?1. These findings highlight that Ru(II) dyads derived from α-oligothiophenes directly appended to 1,10-phenanthroline—namely 2 and 3—possess low-lying 3IL states that are highly photosensitizing, and they may therefore be of interest for photobiological applications such as photodynamic therapy (PDT).
- Monro, Susan,Cameron, Colin G.,Zhu, Xiaolin,Colón, Katsuya L.,Yin, Huimin,Sainuddin, Tariq,Hetu, Marc,Pinto, Mitch,Fuller, Anderson,Bennett, Leah,Roque, John,Sun, Wenfang,McFarland, Sherri A.
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- Peptide-bridged dinuclear Ru(II) complex for mitochondrial targeted monitoring of dynamic changes to oxygen concentration and ROS generation in live mammalian cells
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A novel mitochondrial localizing ruthenium(II) peptide conjugate capable of monitoring dynamic changes in local O2 concentrations within living cells is presented. The complex is comprised of luminescent dinuclear ruthenium(II) polypyridyl complex bridged across a single mitochondrial penetrating peptide, FrFKFrFK-CONH2 (r = d-arginine). The membrane permeability and selective uptake of the peptide conjugate at the mitochondria of mammalian cells was demonstrated using confocal microscopy. Dye co-localization studies confirmed very precise localization and preconcentration of the probe at the mitochondria. This precision permitted collection of luminescent lifetime images of the probe, without the need for co-localizing dye and permitted semiquantitative determination of oxygen concentration at the mitochondria using calibration curves collected at 37 °C for the peptide conjugate in PBS buffer. Using Antimycin A the ability of the probe to respond dynamically to changing O2 concentrations within live HeLa cells was demonstrated. Furthermore, based on lifetime data it was evident that the probe also responds to elevated reactive oxygen species (ROS) levels within the mitochondria, where the greater quenching capacity of these species led to luminescent lifetimes of the probe at longer Antimycin A incubation times which lay outside of the O2 concentration range. Although both the dinuclear complex and a mononuclear analogue conjugated to an octaarginine peptide sequence exhibited some cytotoxicity over 24 h, cells were tolerant of the probes over periods of 4 to 6 h which facilitated imaging. These metal-peptide conjugated probes offer a valuable opportunity for following dynamic changes to mitochondrial function which should be of use across domains in which the metabolic activity of live cells are of interest from molecular biology and drug discovery.
- Martin, Aaron,Byrne, Aisling,Burke, Christopher S.,Forster, Robert J.,Keyes, Tia E.
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- Synthesis of metallo-supramolecular polymers using 5,5′-linked bis(1,10-phenanthroline) ligands
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5,5′-Linked bis(1,10-phenanthroline)s were synthesized as new bidentate ligands by a palladium-catalyzed Suzuki-type cross-coupling reaction. Coordination of the ligands to Cu(II), Ni(II), Ag(I), and Zn(II) ions resulted in metallo-supramolecular polymer formation. The 1:1 complexation of the ligands and the metal ions was confirmed by UV-vis titration experiments. The high molecular weights of more than 105 Da, caused by the high complexation constants, were confirmed by the SEC-Viscometry-RALLS method. Georg Thieme Verlag Stuttgart New York.
- Hossain, Md. Delwar,Higuchi, Masayoshi
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- Novel ruthenium(II) and zinc(II) complexes for two-photon absorption related applications
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Two new fluorene derivatized 1,10-phenanthroline ligands and related tris-chelate Ru(ii) or Zn(ii) coordination complexes have been synthesised. The linear and nonlinear (two-photon induced fluorescence) photophysical measurements have contributed to highlight the possibility to tune the absorption spectral range and excited lifetime, depending on ligand substitution and nature of the metal. More significantly, the observation of two-photon absorption (TPA) associated with long-lived metal-to-ligand charge-transfer (MLCT) excited states in the Ru(ii)-based chromophores, opens a wide range of applications in the near infrared. The Royal Society of Chemistry 2007.
- Girardot,Lemercier,Mulatier,Chauvin,Baldeck,Andraud
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- Palladium Nanoparticles Encapsulated in [M(C19H11N2O2)2·H2O] (M = Co and Mn) as a Potential Catalyst for the Homocoupling of Aryl Halides
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A new ligand, 4-(1,10-phenanthrolin-6-yl)benzoic acid, has been synthesized and employed to prepare new inorganic coordination polymer compounds, [M(C19H11N2O2)2·H2O] (M = Co, Mn). Both the compounds have identical structures formed by the connectivity between octahedral metal centers and the ligand, giving rise to a two-dimensional structure. The 2D structure is interpenetrated by identical units and forms a 2-fold interpenetrated structure. The lattice water molecules can be reversibly removed without altering the gross framework structure. The water removal has been investigated using in situ IR, PXRD, and in situ single-crystal XRD studies. Pd nanoparticles, prepared employing known procedures, were incorporated within the compound. We have successfully encapsulated up to 6.8% of Pd with a particle size of 4.8 ± 0.3 nm in the compound. The Pd@MOF compound was examined for homocoupling of aryl halides, resulting in good yields and recyclability. Magnetic studies indicate antiferromagnetic behavior in both the compounds with good orbital contribution for the cobalt compound.
- Jana, Ajay Kumar,Hota, Raghunandan,Natarajan, Srinivasan
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- Confocal fluorescence microscopy studies of a fluorophore-labeled dirhodium compound: Visualizing metal-metal bonded molecules in lung cancer (A549) cells
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The new dirhodium compound [Rh2(μ-O2CCH 3)2(η1-O2CCH3) (phenbodipy)(H2O)3][O2CCH3] (1), which incorporates a bodipy fluorescent tag, was prepared and studied by confocal fluorescence microscopy in human lung adenocarcinoma (A549) cells. It was determined that 1 localizes mainly in lysosomes and mitochondria with no apparent nuclear localization in the 1-100 μM range. These results support the conclusion that cellular organelles rather than the nucleus can be targeted by modification of the ligands bound to the Rh24+ core. This is the first study of a fluorophore-labeled metal-metal bonded compound, work that opens up new venues for the study of intracellular distribution of dinuclear transition metal anticancer complexes.
- Pe?a, Bruno,Barhoumi, Rola,Burghardt, Robert C.,Turro, Claudia,Dunbar, Kim R.
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- Chemistry on the Complex: Derivatization of TiO4N2-Based Complexes and Application to Multi-Step Synthesis
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The chemistry on octahedral TiO4N2-complexes is described. The Ti(IV)-based precursors are composed of two 3,3’-diphenyl-2,2’-biphenolato ligands (1) and one substituted 1,10-phenanthroline ligand (2-5). The application of imine condensation, palladium-catalyzed C?C bond formation or copper-catalysed azide-alkyne cycloaddition allowed the grafting of various new groups onto these species. In particular Sonogashira reactions permitted to observe an excellent conversion of the starting complexes. This systematic study enabled to compile the factors required to preserve the framework of the complexes in the course of a chemical transformation. Thanks to this chemistry realized on the complex, the Ti(1)2 fragment was used as a protecting group to develop a multi-step synthesis of a bis-phenanthroline compound (12), for which the synthesis without this protection failed. Thus, a dinuclear complex [Ti2(1)4(12)] was first prepared starting from complex precursor bearing an acetylenic function via a Hay coupling reaction. This was followed by a deprotection step affording 12. Overall, this work illustrates how the Ti(1)2 fragment could be an useful tool for the preparation of unprecedented diimine compounds.
- Chaumont, Alain,Kyritsakas, Nathalie,Mobian, Pierre,Scarpi-Luttenauer, Matthieu
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p. 17910 - 17920
(2021/12/09)
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- Turn On of a Ruthenium(II) Photocatalyst by DNA-Templated Ligation
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Here, the synthesis of a RuII photocatalyst by light-directed oligonucleotide-templated ligation reaction is described. The photocatalyst was found to have tremendous potential for signal amplification with >15000 turnovers measured in 9 hours. A templated reaction was used to turn on the activity of this ruthenium(II) photocatalyst in response to a specific DNA sequence. The photocatalysis of the ruthenium(II) complex was harnessed to uncage a new precipitating dye that is highly fluorescent and photostable in the solid state. This reaction was used to discriminate between different DNA analytes based on localization of the precipitate as well as for in cellulo miRNA detection. Finally, a bipyridine ligand functionalized with two different peptide nucleic acid (PNA) sequences was shown to enable template-mediated ligation (turn on of the ruthenium(II) photocatalysis) and recruitment of substrate for templated photocatalysis.
- Anzola, Marcello,Winssinger, Nicolas
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supporting information
p. 334 - 342
(2018/11/25)
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- A O-phenanthrene derivatives and their organic electroluminescent device (by machine translation)
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The present invention provides a O-phenanthrene derivatives and their organic electroluminescent device, relates to organic photoelectric material technical field. The compound preparation method is simple, easily available raw materials, has good thermal stability and chemical stability, while at the same time has very good film-forming property and the cavity transmitting capacity. Such compound has suitable maximum has been molecular orbit level, high T1 value and a high refractive index, as applied to the light-emitting layer in the OLED device, can realize the light-emitting layer of the charge equalization, can markedly improve the luminous efficiency of the device, the service life of the heat resistance and, at the same time also can effectively reduce the driving voltage of the device, is a kind of excellent performance of the OLED material. (by machine translation)
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Paragraph 0058; 0060-0062
(2018/10/19)
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- Heteroleptic Ter-Bidentate Cr(III) Complexes as Tunable Optical Sensitizers
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To exploit Cr(III) coordination complexes as sensitizers in supramolecular energy-converting devices, the latter optical relays should display long-lived excited states, broad emission bands, and tunable spatial and electronic connections to activator units. An ad-hoc versatile strategy has been therefore developed for the preparation of a family of luminescent pseudo-octahedral [CrN6] chromophores made up of ter-bidentate heteroleptic [Cr(phen)2(N-N'′)]3+ complexes, where phen is 1,10-phenanthroline, and N-N′ stands for α,α′-diimine ligands possessing peripheral substituents compatible with both electronic tuning and structure extensions. As long as the ligand field in these [CrN6] chromophores remains sufficiently strong to avoid back-intersystem crossing, photophysical studies indicate that the lifetime of the near-infrared emissive Cr(2E) excited state is poorly sensitive to ligand-based electronic effects. On the contrary, a drop in symmetry, the coupling with high frequency oscillators, and the implementation of sterical constraints in heteroleptic [Cr(phen)2(N-N′)]3+ complexes affect both Cr(2E a? 4A2) energies and Cr(2E) lifetimes. Altogether, [Cr(phen)2(phenAlkyn)]3+ (phenAlkyn = 5-ethynyl-1,10-phenanthroline) and [Cr(phen)2(dpma)]3+ (dpma = di(pyrid-2-yl)(methyl)amine) complexes mirror the favorable photophysical properties of homoleptic [Cr(phen)3]3+ and thus emerge as the best heteroleptic candidates for acting as sensitizers at room temperature, and below 100 K, respectively, in more complicated architectures.
- Doistau, Benjamin,Collet, Guillaume,Bolomey, Emilio Acuna,Sadat-Noorbakhsh, Vida,Besnard, Céline,Piguet, Claude
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p. 14362 - 14373
(2018/11/23)
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- Dual mechanism of action of 5-Nitro-1,10-phenanthroline against mycobacterium tuberculosis
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New chemotherapeutic agents with novel mechanisms of action are urgently required to combat the challenge imposed by the emergence of drug-resistant mycobacteria. In this study, a phenotypic whole-cell screen identified 5-nitro-1,10-phenanthroline (5NP) as a lead compound. 5NP-resistant isolates harbored mutations that were mapped to fbiB and were also resistant to the bicyclic nitroimidazole PA-824. Mechanistic studies confirmed that 5NP is activated in an F420-dependent manner, resulting in the formation of 1,10-phenanthroline and 1,10-phenanthrolin-5-amine as major metabolites in bacteria. Interestingly, 5NP also killed naturally resistant intracellular bacteria by inducing autophagy in macrophages. Structure-activity relationship studies revealed the essentiality of the nitro group for in vitro activity, and an analog, 3-methyl-6-nitro-1,10-phenanthroline, that had improved in vitro activity and in vivo efficacy in mice compared with that of 5NP was designed. These findings demonstrate that, in addition to a direct mechanism of action against Mycobacterium tuberculosis, 5NP also modulates the host machinery to kill intracellular pathogens.
- Kidwai, Saqib,Park, Chan-Yong,Mawatwal, Shradha,Tiwari, Prabhakar,Jung, Myung Geun,Gosain, Tannu Priya,Kumar, Pradeep,Alland, David,Kumar, Sandeep,Bajaj, Avinash,Hwang, Yun-Kyung,Song, Chang Sik,Dhiman, Rohan,Lee, Ill Young,Singh, Ramandeep
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supporting information
(2017/11/04)
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- Synthesis and Photophysical Properties of Triazolyl IrIIINucleosides
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DNA-based nanomaterials are the subject of numerous researches. A series of modified nucleobases were synthesized either to construct a double helix where the natural H-bonded bases are replaced by metal-coordinated liganosides or to introduce a punctual modification inside a natural DNA structure. Thanks to their photophysical and photochemical properties, iridium(III) complexes are of increasing interest in the development of sensors and photoreactants for biochemical applications. In this view, we previously demonstrated that some IrIIIcomplexes are able to photoreact with DNA through photoinduced electron transfer. In this study, we report the synthesis and characterization of nucleosides bearing iridium complexes with unaltered properties compared to their parent complexes.
- Passays, Johan,Rubay, Christophe,Marcélis, Lionel,Elias, Benjamin
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p. 623 - 629
(2017/02/05)
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- Synthesis, photophysical and electrochemical properties of a mixed bipyridyl-phenanthrolyl ligand Ru(II) heteroleptic complex having trans-2-Methyl-2-butenoic acid functionalities
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In this work, two ligands: 4-(trans-2-Methyl-2-butenoic acid)-2,2'-bipyridine) (L1) and 5-(trans-2-methyl-2-butenoic acid)-1,10-phenanthroline (L2), with the corresponding mixed-ligand heteroleptic Ru(II) complex were synthesized and characterized by FT-IR, 1H-, 13C-NMR spectroscopy and elemental analysis. The influence of the mixed functionalized polypyridyl ruthenium(II) complex on the photophysical and electrochemical properties were investigated and compared to individual single-ligand homoleptic complexes. Interestingly, the mixed-ligand complex formulated as [RuL1L2(NCS)2] exhibits broad and intense metal-to-ligand charge transfer (MLCT) absorption with a high molar extinction coefficient (λmax = 514 nm, ε = 69,700 M -1 cm-1), better than those of individual single-ligand complexes, [Ru(L1)2(NCS)2] and [Ru(L2) 2(NCS)2], and a strong photoluminescence intensity ratio in the red region at λem = 686 nm. The electrochemical properties of the complex indicated that the redox processes are ligand-based.
- Adeloye, Adewale O.
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p. 8353 - 8367
(2011/12/15)
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- Photobiological activity of Ru(ll) dyads based on (Pyren-1 -yl)ethynyl derivatives of 1, 10-Phenanthroline
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Several mononuclear Ru(ll) dyads possessing 1, 10-phenanthrollne-appended pyrenylethynylene llgands were synthesized, characterized, and evaluated for their potential in photobiologlcal applications such as photodynamlc therapy (PDT). These complexes interact with DNA via intercalation and photocleave DNA in vitro at submlcromolar concentrations when irradiated with visible light (λirr ≥ 400 nm). Such properties are remarkably sensitive to the position of the ethynylpyrenyl substituent on the 1, 10-phenanthroline ring, with 3-substitutlon showing the strongest binding under all conditions and causing the most deleterious DNA damage. Both dyads photocleave DNA under hypoxic conditions, and this photoactlvity translates well to cytotoxicity and photocytotoxlcity models using human leukemia cells, where the 5- and 3-substituted dyads show photocytotoxiclty at 5-10μM and 10-20μM, respectively, with minimal, or essentially no, dark toxicity at these concentrations. This lack of dark cytotoxicity at concentrations where significant photoactlvity Is observed emphasizes that agents with strong intercalating units, previously thought to be too toxic for phototherapeutic applications, should not be excluded from the arsenal of potential photochemotherapeutic agents under investigation.
- Monro, Susan,Scott, John,Chouai, Abdellatif,Lincoln, Richard,Zong, Ruifa,Thummel, Randolph P.,McFarland, Sherri A.
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body text
p. 2889 - 2900
(2010/05/15)
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- Kinetics of Aquation of 2+ Ions in Aqueous Solutions as a Function of Temperature and Pressure. The Isochoric Controversy and Analysis of Equilibrium and Kinetic Data
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Rate constants are reported for the aquation of 2+ ions in aqueous solutions as a function of temperature, T, and pressure, p, yielding volumes and enthalpies of activation for the rate-determining loss of the first 5-Br-phen ligand.Data describing the dependence of molar volume of water on T and p are analysed to obtain T-p pairs at which the molar volume of water, V*(H2O; 1) equals the molar volume at 298.15 K and 101325 N m-2; i.e. under an isochoric condition which is extrinsic to the aqueous solution containing the iron(II) complex.Kinetic data for the aquation reaction are analysed to obtain rate constants, k, and related activation parameters under corresponding extrinsic isochoric conditions.This quantitative approach is applied to data describing the dependences of equilibrium constants characterising the acid dissociation of ethanoic acid(aq), the first ionization constant for orthophosphoric acid, and self-dissociation of water.The treatment is also applied to kinetic data describing the solvolysis in aqueous solution of benzyl chloride.For the three chemical equilibria the dependences are calculated of lnK, enthalpy ΔrHinfinite and volume of reaction ΔrVinfinite on T at fixed p, on p at fixed T, on T with p changing to keep V*(H2O; 1) constant, and on p with T again changing to hold V*(H2O; 1) constant.Similar treatments are applied to lnk, enthalpies and volumes of activation.The procedures show how the suggestion made by Evans and Polanyi in 1935 can be acted on, at the same time rataining thermodynamic consistency with respect to standard and reference states for solutes in solution.Differences between isochoric *(H2O; 1) and both isobaric and isothermally derived parameters are discussed in terms of the role of solvent structure in controlling reaction and activation.The isochoric *(H2O)> dependence of rate constants on temperature for aquation of the above iron(II) complex differs from the corresponding isobaric dependence.The pattern for the solvolysis in aqueous solutions of benzyl chloride differs from that for the iron(II) complex.The differences are consistent with the changes in hydrophilic-hydrophobic character for a given substrate on going from initial to transition state.
- Blandamer, Michael J.,Burgess, John,Cowles, Heather J.,Horn, Ian M.,Engberts, Jan B. F. N.,et al.
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p. 3733 - 3746
(2007/10/02)
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