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Oskarsson - One of the best experts on this subject based on the ideXlab platform.
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Packing effects on the geometry of neutral platinum(II) complexes due to solvate molecules: the structures of trans-dichlorobis(triphenylarsine)-platinum(II)
Acta crystallographica. Section B Structural science, 2000Co-Authors: Johansson, Otto, Roodt, OskarssonAbstract:A series of structures of trans-dichlorobis(triphenylarsine)platinum(II), recrystallized from four different solvents, have been characterized by X-ray crystallography and were shown to crystallize as different solvates (same metal complex, different crystallization solvents). Their geometric differences induced by packing and solvent molecules were analysed with half-normal probability plots and root-mean-square deviations. The recrystallization solvents used in the investigation were 1,1,1-trichloroethane, dichloromethane, 1,2-Dichloroethane and benzene, and the following crystallization modes were obtained. From 1,1,1-trichloroethane the metal complex crystallizes without solvent as trans-[PtCl2(AsPh3)2] in P2(1)/n with Z = 2, a = 9.271 (2), b = 19.726 (4), c = 9.830 (2) A, beta = 111.83 (3)degrees, V = 1668.8 (6) A3, R = 0.0262, and from dichloromethane with two solvent molecules as trans-[PtC12(AsPh3)2].2CH2C12 in Pbca with Z= 4, a = 20.582 (4), b = 8.146 (2), c = 23.491 (5) A, V = 3938.5 (14) A3 and R = 0.0316. From Dichloroethane it crystallizes with one solvent molecule as trans-[PtC12(AsPh3)2].C2H4C12 in P1 with Z = 1, a = 9.390 (2), b= 9.548 (2), c = 11.931 (2) A, alpha = 109.70 (3), beta = 108.26 (3), gamma = 98.77 (3) , V= 915.6 (3) A3, R = 0.0390, and from benzene with half a solvent molecule as trans- [PtC12(AsPh3)2].0.5C6H6 in P2(1)/n with Z = 4, a = 11.778 (2), b = 18.712 (4), c = 16.647 (3) A, beta = 104.78 (3) , V= 3547.3 (12) A3 and R = 0.0303. In all four compounds platinum(II) coordinates to triphenylarsine and chloride in a pseudo-square-planar trans configuration. The Pt-As distances are in the range 2.4104 (4)-2.3923 (4) A and the Pt-C distances are in the range 2.309 (2)-2.2839 (9) A. The solvents have a large influence on the packing, resulting in different space groups or different occupancies in the same space group. Half-normal probability plots show that the largest geometric differences, within the metal complex, are in the bond and torsion angles around the As-C bonds. Very similar torsion angles were observed around the Pt-As bond for all the structures, except for one AsPh3 ligand in the benzene solvate, which differs by about 10 from the others. The metal-donor bond distance varies by as much as 0.019 and 0.025 A (95% confidence interval) for Pt-As and Pt-C1, respectively. The variations are essentially caused by intermolecular interactions. Packing efficiency is expressed as the volume filled by each metal complex in the unit cell and is calculated by subtracting the sum of the solvent molecule volumes from the total volume of the unit cell and then dividing by Z. The efficiency is largest in the Dichloroethane solvate and smallest in the non-solvated compound, with a difference of approximately 22 A3 per metal complex.
Åke Oskarsson - One of the best experts on this subject based on the ideXlab platform.
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Packing effects on the geometry of neutral platinum(II) complexes due to solvate molecules: the structure of trans-dichlorobis(triphenylarsine)platinum(II)
Acta Crystallographica Section B Structural Science, 2000Co-Authors: Maria H. Johansson, Stefanus Otto, Andreas Roodt, Åke OskarssonAbstract:A series of structures of trans-dichlorobis(triphenylarsine)platinum(II), recrystallized from four different solvents, have been characterized by X-ray crystallography and were shown to crystallize as different solvates (same metal complex, different crystallization solvents). Their geometric differences induced by packing and solvent molecules were analysed with half-normal probability plots and root-mean-square deviations. The recrystallization solvents used in the investigation were 1,1,1-trichloroethane, dichloromethane, 1,2-dichloroethane and benzene, and the following crystallization modes were obtained. From 1,1,1-trichloroethane the metal complex crystallizes without solvent as trans-[PtCl2(AsPh3)2] in P21/n with Z = 2, a = 9.271 (2), b = 19.726 (4), c = 9.830 (2) A, β = 111.83 (3)°, V = 1668.8 (6) A3, R = 0.0262, and from dichloromethane with two solvent molecules as trans-[PtCl2(AsPh3)2]·2CH2Cl2 in Pbca with Z = 4, a = 20.582 (4), b = 8.146 (2), c = 23.491 (5) A, V = 3938.5 (14) A3 and R = 0.0316. From Dichloroethane it crystallizes with one solvent molecule as trans-[PtCl2(AsPh3)2]·C2H4Cl2 in P\overline 1 with Z = 1, a = 9.390 (2), b = 9.548 (2), c = 11.931 (2) A, α = 109.70 (3), β = 108.26 (3), γ = 98.77 (3)°, V = 915.6 (3) A3, R = 0.0390, and from benzene with half a solvent molecule as trans-[PtCl2(AsPh3)2]·0.5C6H6 in P21/n with Z = 4, a = 11.778 (2), b = 18.712 (4), c = 16.647 (3) A, β = 104.78 (3)°, V = 3547.3 (12) A3 and R = 0.0303. In all four compounds platinum(II) coordinates to triphenylarsine and chloride in a pseudo-square-planar trans configuration. The Pt—As distances are in the range 2.4104 (4)–2.3923 (4) A and the Pt—Cl distances are in the range 2.309 (2)–2.2839 (9) A. The solvents have a large influence on the packing, resulting in different space groups or different occupancies in the same space group. Half-normal probability plots show that the largest geometric differences, within the metal complex, are in the bond and torsion angles around the As—C bonds. Very similar torsion angles were observed around the Pt—As bond for all the structures, except for one AsPh3 ligand in the benzene solvate, which differs by about 10° from the others. The metal–donor bond distance varies by as much as 0.019 and 0.025 A (95% confidence interval) for Pt—As and Pt—Cl, respectively. The variations are essentially caused by intermolecular interactions. Packing efficiency is expressed as the volume filled by each metal complex in the unit cell and is calculated by subtracting the sum of the solvent molecule volumes from the total volume of the unit cell and then dividing by Z. The efficiency is largest in the Dichloroethane solvate and smallest in the non-solvated compound, with a difference of approximately 22 A3 per metal complex.
Santos Otin - One of the best experts on this subject based on the ideXlab platform.
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Excess volumes of (1-chlorobutane or 1,2-Dichloroethane or tetrachloromethane or 1,1,2,2-tetrachloroethane + dichloromethane or trichloromethane) and of (dichloromethane + trichloromethane) at the temperature 298.15 K
The Journal of Chemical Thermodynamics, 1991Co-Authors: Manuela Artal, J. Muñoz Embid, Inmaculada Velasco, Santos OtinAbstract:The excess molar volumes VEm of {x(ClCH2CH2CH2CH3 or ClCH2CH2Cl or CCl4 or Cl2CHCHCl2) + (1 − x)(CH2Cl2 or CHCl3)} and of {(xCH2Cl2 + (1 − x)CHCl3} have been determined experimentally as a function of the mole fraction x from density measurements at the temperature 298.15 K. The excess molar volumes are negative except for mixtures containing tetrachloromethane and for (1-chlorobutane + dichloromethane). (Dichloromethane + trichloromethane) shows an almost “ideal” volumetric behaviour.
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excess volumes of 1 chlorobutane or 1 2 Dichloroethane or tetrachloromethane or 1 1 2 2 tetrachloroethane dichloromethane or trichloromethane and of dichloromethane trichloromethane at the temperature 298 15 k
The Journal of Chemical Thermodynamics, 1991Co-Authors: Manuela Artal, Inmaculada Velasco, Munoz J Embid, Santos OtinAbstract:The excess molar volumes VEm of {x(ClCH2CH2CH2CH3 or ClCH2CH2Cl or CCl4 or Cl2CHCHCl2) + (1 − x)(CH2Cl2 or CHCl3)} and of {(xCH2Cl2 + (1 − x)CHCl3} have been determined experimentally as a function of the mole fraction x from density measurements at the temperature 298.15 K. The excess molar volumes are negative except for mixtures containing tetrachloromethane and for (1-chlorobutane + dichloromethane). (Dichloromethane + trichloromethane) shows an almost “ideal” volumetric behaviour.
Rajni M. Patel - One of the best experts on this subject based on the ideXlab platform.
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polyetherketones synthesis characterization and antimicrobial activity
International Journal of Polymeric Materials, 2005Co-Authors: Milan V Patel, J. N. Patel, Mitul B Dolia, Rajni M. PatelAbstract:ABSTRACT Friedel-Crafts polyetherketones were prepared from o-chlorophenol, 1,4-phenylenedioxy diacetylchloride (1,4-PDC), chloroacetyl chloride (CAC), 1,2-Dichloroethane (DCE), and dichloromethane (DCM) using anhydrous aluminium chloride (AlCl3) as catalyst and carbon disulfide (CS2) as solvent. These resins were characterized by IR spectroscopy and gel permeation chromatography. Carius method was employed to obtain the percentage of chlorine content in the resins. The kinetic parameters for the thermal behavior of the resins were evaluated from thermogravimetry (TG) using Broido method. Differential scanning calorimetry (DSC) thermograms of these resins were also obtained. All the polyetherketones were tested for their antimicrobial properties against bacteria, fungi, and yeast. It was observed that most of the polyetherketones synthesized could be used as antibacterial and antifungal agents.
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synthesis characterization and thermal properties of polyetherketones prepared from m chloroanisole and evaluating their microbial activity
2004Co-Authors: Milan V Patel, Rajni M. Patel, Pravin PatelAbstract:1,4-phenylenedioxy diacetylchloride (1,4-PDC), chloroacetyl chloride (CAC), 1,2-Dichloroethane (DCE) and dichloromethane by Friedel-Crafts reaction using anhydrous AlCl3 as a catalyst and CS2 as a solvent. The polyetherketones were characterized by IR spectra and gel permeation chromatography (GPC). The kinetic parameters for the thermal decomposition reaction were evaluated by the methods of Broido and Doyle. All the polyetherketones were tested for their biological activity against bacteria, fungi and yeast strains. The results show that most of the polyetherketones can be used as antibacterial and antifungal agents. Milan V. Patel, Rajni M. Patel, and Pravin M. Patel
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Friedel-Crafts Polyetherketones: Synthesis, Characterization and Antimicrobial Properties
Journal of Polymer Research, 2003Co-Authors: Shveta Joshi, Rajni M. Patel, P. M. PatelAbstract:Low molecular weight Friedel-Crafts polyetherketones (PEK) were prepared from o-chloro anisole, 1,4-phenylenedioxy diacetychloride (1,4-PDC), chloroacetylchloride (CAC), 1,2-Dichloroethane (DEC) and dichloromethane (DCM) using anhydrous AlCl_3 as catalyst and CS_2 as solvent. The polyetherketones were characterized by IR spectra and Gel permeation chromatography (GPC). The kinetic parameters for the thermal behaviour of the resins were obtained from thermo gravimetric analysis (TGA) using the Broido and Doyle method. Differential scanning calorimetry (DSC) traces were employed to obtain heat of fusion. All the polyetherketones were tested for their biological activity against bacteria, fungi and yeast. It was observed that most of the polyetherketones synthesized can be used as antibacterial and antifungal agents.
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Synthesis, thermal properties and antibacterial activity of polyketones
International Journal of Polymeric Materials, 2001Co-Authors: P. M. Patel, B. V. Patel, Rajni M. PatelAbstract:Polyketones were prepared by the Friedel-Craft reaction from 1,3-dimethoxy benzene, chloroacetic acid and dichloroalkanes, i.e., dichloromethane and 1,2-dicholoroethane. The polyketones were characterized by IR spectra and vapour pressure osmometry. The thermal properties were studied by the thermogravimetry and differential scanning calorimetry. The kinetic parameters for the thermal decomposition reaction were evaluated by the methods of Broido and Doyle. The synthesized polylaketones shows antimicrobial properties against bacteria, fungi and yeast.
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Synthesis, Thermal Behaviour and Biological Activity of Chlorine Containing Polyketones
International Journal of Polymeric Materials, 1998Co-Authors: Bhavini T. Patel, Rajni M. PatelAbstract:Abstract Chlorine containing compounds are known to possess biological activity. This observation prompted us to synthesis Friedel-Crafts polyketones from o-chlorophenol, chloroacetyl chloride, 1,2-Dichloroethane and dichloromethane using anhydrous aluminium chloride as catalyst and nitrobenzene (PhNO2) as a solvent. The IR spectral data of these compounds indicates the presence of carbonyl and chlorine group in the resin backbone. The kinetic parameters for the thermal decomposition of the resins were evaluated from TG and DSC thermograms using methods of Broido and Doyle. Microbial study indicates the ability of the polyketone to inhibit the growth of selected species of bacteria, fungi and yeast.
Dick B. Janssen - One of the best experts on this subject based on the ideXlab platform.
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Metabolism of mono- and dihalogenated C1 and C2 compounds by Xanthobacter autotrophicus growing on 1,2-Dichloroethane
Biodegradation, 2007Co-Authors: M Torz, Piet Wietzes, Venko Beschkov, Dick B. JanssenAbstract:The conversion of and toxic effects exerted by several mono- and dihalogenated C1 and C2 compounds on cultures of Xanthobacter autotrophicus GJ10 growing on 1,2-Dichloroethane were investigated. Bromochloromethane, dibromomethane and 1-bromo-2-chloroethane were utilized by strain GJ10 in batch culture as a cosubstrate and sole carbon source. The rate of degradation of dihalomethanes by whole cells was lower than that of 1,2-Dichloroethane, but a significant increase of the rate of dihalomethane biodegradation was observed when methanol or ethanol were added as a cosubstrate. Products of the degradation of several tested compounds by haloalkane dehalogenase were analyzed and a new metabolic pathway based on hydrolytic conversion to formaldehyde was proposed for the dihalomethanes. Strain GJ10 growing on 1,2-Dichloroethane converted 2-fluoroethanol and 1-chloro-2-fluoroethane to 2-fluoroacetate, which was tolerated up to a concentration of 2.5 mM. On the basis of the results from batch cultures an inert (dichloromethane), a growth-supporting (dibromomethane) and a toxic (1,2-dibromoethane) compound were selected for testing their effects on a continuous culture of strain GJ10 growing on 1,2-Dichloroethane. The compounds were added as pulses to a steady-state chemostat and the response of the culture was followed. The effects varied from a temporary decrease in cell density for dibromomethane to severe toxicity and culture washout with 1,2-dibromoethane. Our results extend the spectrum of halogenated C1 and C2 compounds that are known to be degraded by strain GJ10 and provide information on toxic effects and transformation of compounds not serving as a carbon source for this bacterium.
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transformation kinetics of chlorinated ethenes by methylosinus trichosporium ob3b and detection of unstable epoxides by on line gas chromatography
Applied and Environmental Microbiology, 1996Co-Authors: Vlie J Van Hylckama, W De Koning, Dick B. JanssenAbstract:A rapid and accurate method for the determination of transformation kinetics of volatile organic substrates was developed. Concentrations were monitored by on-line gas chromatographic analysis of the headspace of well-mixed incubation mixtures. With this method, the kinetics of transformation of a number of C(inf1) and C(inf2) halogenated alkanes and alkenes by Methylosinus trichosporium OB3b expressing particulate methane monooxygenase or soluble methane monooxygenase (sMMO) were studied. Apparent specific first-order rate constants for cells expressing sMMO decreased in the order of dichloromethane, vinyl chloride, cis-1,2-dichloroethene, trans-1,2-dichloroethene, 1,1-dichloroethene, trichloroethene, chloroform, and 1,2-Dichloroethane. During the degradation of trichloroethene, cis-1,2-dichloroethene, trans-1,2-dichloroethene, and vinyl chloride, the formation of the corresponding epoxides was observed. The epoxide of vinyl chloride and the epoxide of trichloroethene, which temporarily accumulated in the medium, were chemically degraded according to first-order kinetics, with half-lives of 78 and 21 s, respectively. Cells expressing sMMO actively degraded the epoxide of cis-1,2-dichloroethene but not the epoxide of trans-1,2-dichloroethene. Methane and acetylene inhibited degradation of the epoxide of cis-1,2-dichloroethene, indicating that sMMO was involved.
