摘要:

AbstractA novel technique is described for forming ground‐state SOX3Σradicals free of reactive impurities in a discharge‐flow system. Mass spectrometric detection of SO and ClO free radicals has been used to study the kinetics of the following reactions at

ISSN:0538-8066    

DOI:10.1002/kin.550120202

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractDemetallation rates of α,β,γ,δ‐tetrakis(p‐sulfophenyl)porphiniron(III) in hydrochloric acid–ethanol–water, perchloric acid–ethanol–water, and sulfuric acid–alcohol–water media were determined. For a given acidity valueH0the order of the rates for the three acids was HCl>H2SO4>HClO4. This is also the order for complex formation between acid anion and iron(III). Consequently ligands as well as protons are involved in the breaking of bonds between the metal and the porphyrin leading to the formation of the activated complex. The logkvalues for HCl and HClO4media were not linearly related to the Hammett acidity function as they were for sulfuric acid–ethanol–water media. The average ΔH‡ and ΔS‡values for the HCl media were 18.4 ± 1.4 kcal/mol and 19 ± 3 cal K mol, respectively, in very close agreement with those for H2SO4media despite the difference inH0dependence. For H2SO4–alcohol–water media the order of the rates was butanol>propanol>ethanol with little

ISSN:0538-8066    

DOI:10.1002/kin.550120203

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractAn example of a sequence of competing first‐order reactions, leading to a common product, has been found for the sulfodeacylation of acetylpropionylmesitylene. The basic reaction scheme is Scheme land a kinetic analysis of the component rate constants allows an estimate to be made of the concentrations of the reactant and products as a function of time. In the present system the total concentration of the intermediatesB, C, andDnever exceeds 0.26% at 25°C, and therefore the kinetics, which were followed spectrophotometrically, were essentially of the conversion of substrateAto the final productE.The kinetics of protiodeacylation have been measured, over a range of temperatures, of propionyl‐, dipropionyl‐, and acetylpropionylmesitylenes in 89.8% (w/w) sulfuri

ISSN:0538-8066    

DOI:10.1002/kin.550120204

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractThe decomposition of CH3CD2CH3was studied from 713 to 853 K at pressures of 98–466 torr. The values ofk1/k2= 2.08 ± 0.05 andk3/k4= 2.04 ± 0.66 were found independent of temperature by measuring the ratios of CH4/CH3D and CH3CHD2/CH3CD3, respectively, for the following reactions:. Isomerization of CH3CDCH3was detected by measuring CHDCH2formed from the isomerized radical. The expression ofk21/k22was found to bewherek21andk22are the rate constants of. The results and conclusions are discussed and compared with previous wo

ISSN:0538-8066    

DOI:10.1002/kin.550120205

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractA method is presented for the prediction of rate coefficients and Arrhenius parameters for bimolecular hydrogen atom transfer reactions A + BC → AB + C. The treatment sets out from structural considerations of the complex A ⃛ B ⃛ C and calculates the energy of the complex along the reaction path from empirical functions for a bonding energy term and an endgroup contribution. The treatment proceeds by assuming ultrasimple transition state models and assigning the force constants and vibrational frequencies. Finally the rate coefficient and Arrhenius parameters are obtained on the basis of separable activated complex theory. Application of the method requires known properties of reactant and product molecules and does not demand the use of adjustable parameters. The relation and differences between this method and the BEBO treatment as well as Zavitsas' method are dealt

ISSN:0538-8066    

DOI:10.1002/kin.550120206

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

ISSN:0538-8066    

DOI:10.1002/kin.550120207

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

ISSN:0538-8066    

DOI:10.1002/kin.550120201

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY