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1.
The kinetics of the reactions of benzene-substituted N-isobutylanilines 1a—h with 3-nitrobenzenesulfonyl chloride in propan-2-ol was studied at 298 K. To analyze the reactivities of compounds 1a—h in the arylsulfonylation reactions and substantiate the possible mechanism of these reactions, the geometric, electronic, and energy characteristics of the reagents and a series of model compounds were calculated by the semiempirical quantum-chemical AM1 and PM3 methods. The rate of arylsulfonylation of N-isobutylaniline and its derivatives increases directly proportional to the contributions of the s and p z orbitals of the N atoms to HOMO of amine and of the S atoms to LUMO of sulfonyl chloride. The coefficients of these AOs can be considered as the reactivity indices of the reagents used for arylsulfonylation of substituted N-isobutylanilines with aromatic sulfonyl chlorides. It was proposed that the reaction under study is orbital-controlled.  相似文献   

2.
Kinetics of arenesulfonylation of glycine, D,L-α-alanine, and D,L-valine with 3-nitrobenzenesulfonyl chloride were studied in solvent systems water-1,4-dioxane and water-2-propanol at water content 40 wt % and at different temperatures (298–313 ?). The effective values of activation parameters of the reaction were calculated. The kinetic characteristics of the studied reactions were compared with the corresponding data for glycine, alanine, and valine in reaction with benzoyl chloride in aqueous dioxane.  相似文献   

3.
Secondary aliphatic-aromatic amines were synthesized by hydrogenative amination of aliphatic aldehydes with aromatic amines. The kinetics of arylsulfonation of the resulting alkylarylamines with benzenesulfonyl chloride and its monosubstituted derivatives in 2-propanol at 298 K were studied. The activation parameters of the reaction of ring-substituted N-isobutylanilines with 3-nitrobenzenesulfonyl chloride were determined.  相似文献   

4.
Abstract  Solvatochromic parameters (E T N, normalized polarity parameter; π*, dipolarity/polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (IL; 2-hydroxyethylammonium formate) at 25 °C. In all solutions except aqueous solution, E T N values of the media increase abruptly with the ILs mole fraction and then increase gradually to the value of pure IL. A synergistic behavior is observed for the α parameter in all solutions. The behavior of π* and β are nearly ideal for all solutions except for solutions of methanol with the IL. The applicability of nearly ideal combined binary solvent/Redlich–Kister equation was proved for the correlation of various solvatochromic parameters with solvent composition. The correlation between the calculated and the experimental values of various parameters was in accordance with this model. Solute–solvent and solvent–solvent interactions were applied to interpret the results. Graphical Abstract  Predicted values of solvatochromic parameters (SP) (E T N, normalized polarity parameter; π*, dipolarity/polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) from the correlation equations versus its experimental values for binary mixtures of 2-hydroxyethylammonium formate with water, methanol, ethanol, propan-1-ol and propan-2-ol.   相似文献   

5.

Abstract  

Solvatochromic parameters (E T N, normalized polarity parameter; π*, dipolarity/polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (IL; 2-hydroxyethylammonium formate) at 25 °C. In all solutions except aqueous solution, E T N values of the media increase abruptly with the ILs mole fraction and then increase gradually to the value of pure IL. A synergistic behavior is observed for the α parameter in all solutions. The behavior of π* and β are nearly ideal for all solutions except for solutions of methanol with the IL. The applicability of nearly ideal combined binary solvent/Redlich–Kister equation was proved for the correlation of various solvatochromic parameters with solvent composition. The correlation between the calculated and the experimental values of various parameters was in accordance with this model. Solute–solvent and solvent–solvent interactions were applied to interpret the results.  相似文献   

6.
A regio- and stereospecific synthesis of 11E-tetradecen-1-ol and its derivatives, which are pheromone components of many insect species ofLepidoptera order, by means of a reaction of methylmagnesium cuprate reagent with 1,12-tridecadien-3-yl acetate by theS N2′ mechanism, was carried out. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1074–1075, May, 1997.  相似文献   

7.
The kinetics of the anation reaction of cis-diaquo-bis-oxalatochromate(III) ion by DL-alanine has been studied spectrophotometrically in the pH range 3.8 to 7.3, where DL-alanine remains in zwitterionic form. A second-order rate law has been established. Reaction rates in three different ethanol-water mixtures were measured. In each solvent medium the anation rate is higher as compared to water exchange reaction at a particular temperature. The activation parameters (gDH# and ΔS#) in different ethanol-water mixtures were obtained from Eyring plots. ΔG#(ΔH#TΔS #) values were calculated in each solvent medium and compared with that of the isotopic water exchange process. A reaction mechanism involving theS N2 path has been suggested.  相似文献   

8.
Dec-1-ene oligomerization in the presence of an aluminum—1-dodecyl chloride system was studied. A mixture of low-molecular-weight oligodecenes containing 25–40 wt.% dimers and 30–52 wt.% dec-1-ene trimers is formed at the molar ratios RCl/A1 = 0.5–1.5. The oligomerization was assumed to occur under the action of cationic active sites, which are formed during the reaction of 1-chlorodedecane with aluminum. At temperatures of 120–130°C and molar ratios RCl/A1 = 0.5–1.5 metallic aluminum completely dechlorinates 1-chlorododecane in a dec-1-ene medium. The character of the effect of highly dispersed Al and the RCl/A1 molar rato on the fractional composition and chlorine content in oligodecenes was revealed. The latter are formed by an aluminum—tert-butyl chloride system used in the industrial oligomerization of dec-1-ene. A mechanism of Al dissolution by alkyl chlorides with the simultaneous dechlorination of alkyl chloride and formation of cationic active sites in A1-RCl systems was proposed to explain the results obtained. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 661–665, March, 2008.  相似文献   

9.
Amphiphilic diblock copolymers consisting of 2-(N, N-dimethylamino)ethyl methacrylate (DMAEMA, abbreviated as DMA) and stearyl methacrylate (SMA) with different degrees of polymerization and compositions were prepared by reversible addition–fragmentation chain transfer (RAFT) copolymerization. The composition and chemical structures of (co)polymers were confirmed by the measurements of 1H NMR spectroscopy and gel permeation chromatography (GPC). The self-aggregating structures of amphiphilic diblock copolymers with the concentration of 0.1~0.3 wt.% in THF/water mixed solvent was investigated by transmission electron microscopy (TEM) and dynamic light scattering (DLS). It was found that both the morphologies and aggregating particle size resulted from the amphiphilic diblock copolymers depended on the variation of pH values, the lengths of the hydrophobic PSMA chains, and the weight ratio of THF/water mixed solvent.  相似文献   

10.
The effect of hydrostatic pressure below 1000 kg cm−2 on the rate of reactions of o-and p-nitrophenylsulfenyl chlorides with styrene and cyclohexene was studied. The activation and reaction volumes (cm3 mol−1) for the reactions of o-nitrophenylsulfenyl chloride with styrene in acetonitrile (−23.1 and −23.6), 1,2-dichloroethane (−29.2 and −24.7), chlorobenzene (no, −20.2), and anisole (−25.1 and −21.2) and for the reaction of p-nitrophenylsulfenyl chloride with styrene in carbon tetrachloride (−39.5±1.5 and −22.0) were determined. In carbon tetrachloride the activation volumes for the reactions of cyclohexene with o-and p-nitrophenylsulfenyl chlorides (−37.7±2.0 and −40.9±1.2 cm3 mol−1, respectively) are almost the same and coincide with the data for the reactions with styrene. The considerable decrease in the volume of the transition state in the nonpolar solvent is considered as a consequence of the enhanced electrostriction of carbon tetrachloride in the solvate sphere of the transition state of the reaction, which excludes the nonpolar transition state of the sulfuran type. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 477–480, March, 2007.  相似文献   

11.
Reactions of dialkyl phosphorochloridites with 3-(N-benzylideneamino)propan-1-ol follow two pathways giving rise to linear dialkyl 1-(3-chloropropylamino)benzylphosphonates and diastereomeric cyclic 2-alkoxy-2-oxo-3-phenyl-1,4,2-oxazaphosphepanes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1453–1455, June, 2005.  相似文献   

12.
The kinetics of oxidation of a series of alcohols (propan-2-ol, 2-methylpropan-1-ol, butan-1-ol, butan-2-ol, 3-methylpentan-1-ol, heptan-4-ol, decan-2-ol, cyclohexanol, borneol) by chlorine dioxide in organic solvents was studied using spectrophotometry. The reaction is described by the second-order rate equation w = k[ROH][ClO2]. The rate constants were measured in the range of 10–60 °C, and the activation parameters of the processes were calculated. The products were identified, and the yields were determined.  相似文献   

13.
Methylene-bis[N′-oxydiazene-N-(β-hydroxyalkyl)N-oxides] were synthesized by the reaction of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with diahalomethanes. The effect of the nature of the starting reagents and the reaction condtions on the yields of the target compounds was studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2266–2269, November, 1998.  相似文献   

14.
The enthalpies of mixing of acetonitrile with formamide,N-methylformamide,N,N-dimethylformamide, and hexamethylphosphoric triamide were measured in the temperature interval from 283.15 to 328.15 K. The enthalpy coefficients of binary and ternary interactions were calculated by the methods of the McMillan-Mayer theory. The contributions to the enthalpy of solution due to the formation of a cavity in the solvent, Δcav H°, and those due to the interaction of the solute with the solvent, Δint H°, were determined. The enthalpies of the specific and non-specific solvation of acetonitrile in the corresponding amides were calculated. Specific interactions were found to contribute the most to the solvation enthalpy of acetonitrile. The obtained values were compared with analogous values for solutions of acetonitrile in water and alcohols. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 289–293, February, 1997.  相似文献   

15.
A new xanthone (1, 1,7-dihydroxy-2-methoxyxanthone), in addition to the known metabolites 1,7-dihydroxyxanthone (2), 24(R)-stigmast-7,22 (E)-dien-3α-ol (3), and 1,7-dimethoxyxanthone (4), was isolated from the roots of Securidaca inappendiculata. Compounds 1–4 were evaluated by anti-HIV assay and 1–3 showed anti-HIV-1inhibitory activity in vitro. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 348–349, July–August, 2008.  相似文献   

16.
A method for the synthesis of 2-substitutedN, N′-diacylimidazolidines was developed. The method is based on the reactions of acylating reagents (carboxylic acid chlorides and anhydrides, sulfonic acid chlorides, a carbamic acid chloride, and ethyl chlorocarbonate) with Schiff's bases prepared by the reaction ofN-acylethylenediamines with aldehydes. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 5, pp. 896–900, May, 2000.  相似文献   

17.
A solid complex Eu(C5H8NS2)3(C12H8N2) has been obtained from reaction of hydrous europium chloride with ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phen⋅H2O) in absolute ethanol. IR spectrum of the complex indicated that Eu3+ in the complex coordinated with sulfur atoms from the APDC and nitrogen atoms from the o-phen. TG-DTG investigation provided the evidence that the title complex was decomposed into EuS. The enthalpy change of the reaction of formation of the complex in ethanol, Δr H m θ(l), as –22.214±0.081 kJ mol–1, and the molar heat capacity of the complex, c m, as 61.676±0.651 J mol–1 K–1, at 298.15 K were determined by an RD-496 III type microcalorimeter. The enthalpy change of the reaction of formation of the complex in solid, Δr H m θ(s), was calculated as 54.527±0.314 kJ mol–1 through a thermochemistry cycle. Based on the thermodynamics and kinetics on the reaction of formation of the complex in ethanol at different temperatures, fundamental parameters, including the activation enthalpy (ΔH θ), the activation entropy (ΔS θ), the activation free energy (ΔG θ), the apparent reaction rate constant (k), the apparent activation energy (E), the pre-exponential constant (A) and the reaction order (n), were obtained. The constant-volume combustion energy of the complex, Δc U, was determined as –16937.88±9.79 kJ mol–1 by an RBC-II type rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, Δc H m θ, and standard enthalpy of formation, Δf H m θ, were calculated to be –16953.37±9.79 and –1708.23±10.69 kJ mol–1, respectively.  相似文献   

18.
The reaction of nicotinoyl chloride with ethylene glycol mononitrate yielded the previously unknown 2-nitroxyethyl nicotinate. The resulting ester was used as a ligand in the reaction with PdCl2 for preparing a new complex,trans-bis(2-nitroxyethyl nicotinate-N)dichloropalladium(ii). The structures of the ligand and the complex were established by X-ray structural analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 527–530, March, 1998.  相似文献   

19.
The reaction ofN,N′-bis(2-nitroxyethyl)pyridine-2,6-dicarboxamide with PdCl2 afforded previously unknowncis-(N-2-nitroxyethylpicolinamide-N,N′)dichloropalladium(II) andcis-[2-(2-pyridyl)-2-oxazoline-N,N′]dichloropalladium(II), which were isolated as a cocrystallizate of the molecular compounds. Its structure was established by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1604–1606, August, 1999.  相似文献   

20.
An enantioselective (ee−50%) four-step synthesis of (S)-6-methylhept-5-en-2-ol (“sulcatol”), which is the aggregation pheromone ofGnathotrichus sulcatus, from 3S,7-dimethylocta-1,6-diene was developed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 713–717, April, 2000.  相似文献   

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