The Kinetics of the Insertion Reaction of Tin(II) Chloride with Hexacarbonylbis(triphenylphosphite)dicobalt

1974 ◽  
Vol 52 (22) ◽  
pp. 3773-3777 ◽  
Author(s):  
Peter Fowler Barrett
Keyword(s):  
Electron Acceptor ◽  
Activation Enthalpy ◽  
Visible Spectrum ◽  
Insertion Reaction ◽  
Two Stage ◽  
Temperature Range ◽  
Metal Metal ◽  
Enthalpy And Entropy ◽  
Kinetics Of

The kinetics of the thermal insertion reaction of SnCl2 with the metal–metal bonded complex [P(OC6H5)3Co(CO)3]2 have been studied by following the change in the visible spectrum in THF over the temperature range 35.0 to 55.0 °C. The activation enthalpy and entropy for the reaction are 24.7 ± 0.4 kcal/mol and 2.4 ± 1.3 cal mol−l deg−1 respectively. The data are consistent with a two-stage mechanism identical to that proposed for the corresponding reaction with [P(n-C4H9)3Co(CO)3]2 and from a comparison of the two reactions it is concluded that the cobalt–cobalt bond is slightly weakened when tributylphosphine is replaced by the better π-electron acceptor triphenylphosphite. The insertion products [LCo(CO)3]2SnCl2 are shown to undergo further reaction with [LCo(CO)3]2 to form [LCo(CO)3]3SnCl (L = CO, P(n-C4H9)3, P(OC6H5)3).

The Kinetics of the Insertion Reaction of Tin(II) Chloride with a Mono-substituted Derivative of Cyclopentadienyliron Dicarbonyl Dimer

1972 ◽  
Vol 50 (7) ◽  
pp. 972-976 ◽  
Author(s):  
P. F. Barrett ◽  
W. J. Jacobs
Keyword(s):  
Activation Enthalpy ◽  
Visible Spectrum ◽  
Insertion Reaction ◽  
Triphenyl Phosphite ◽  
Two Stage ◽  
Temperature Range ◽  
Metal Metal ◽  
Iron Iron ◽  
Kinetics Of

The kinetics of the thermal insertion reaction of SnCl2 with the metal–metal bonded complex (π-C5H5)2Fe2(CO)3P(OC6H5)3 have been studied by following the change in the visible spectrum in THF over the temperature range 40.0 to 55.0 °C. The data are consistent with a two-stage mechanism involving the formation of an intermediate in which the iron–iron bond has been broken but the carbonyl bridges are left intact. From the activation enthalpy of 23.4 ± 0.5 kcal/mol for the formation of the intermediate it is concluded that the triphenyl phosphite has brought about a weakening of the iron–iron bond.

The kinetics of the thermal insertion reaction of tin(II) halides with cyclopentadienyliron dicarbonyl dimer

1970 ◽  
Vol 48 (21) ◽  
pp. 3300-3303 ◽  
Author(s):  
P. F. Barrett ◽  
Kenneth K. W. Sun
Keyword(s):  
Activation Energy ◽  
Kinetic Data ◽  
Activation Enthalpy ◽  
Visible Spectrum ◽  
Nucleophilic Attack ◽  
Insertion Reaction ◽  
Activation Entropy ◽  
Kcal Mole ◽  
Metal Metal ◽  
Kinetics Of

The kinetics of the thermal insertion reaction of SnBr2 and SnCl2 with the metal–metal bonded dimer [π-C5H3Fe(CO)2]2 have been studied by following the change in the visible spectrum. The kinetic data are consistent with a two-stage mechanism involving the formation of a carbonyl-bridged intermediate followed by nucleophilic attack by the halides on this intermediate. The formation of the intermediate requires an activation enthalpy of 38.0 ± 1.0 kcal/mole, and an activation entropy of 45.5 + 1.5 cal mole−1 deg−1. The activation energy required to break the Fe—Fe bond is estimated to be about 32 kcal/mole.

The Kinetics of the Thermal Insertion Reaction of Tin(II) Halides with Cyclopentadienylnickel Carbonyl Dimer

1971 ◽  
Vol 49 (16) ◽  
pp. 2627-2630 ◽  
Author(s):  
P. F. Barrett ◽  
Ronald R. Clancy
Keyword(s):  
Kinetic Data ◽  
Activation Enthalpy ◽  
Insertion Reaction ◽  
Activation Entropy ◽  
Metal Bond ◽  
Metal Metal ◽  
Kinetics Of ◽  
Direct Attack ◽  
Bimolecular Mechanism

The kinetics of the thermal insertion of SnCl2 and SnBr2 into the metal–metal bond of [π-C5H5NiCO]2 have been studied. On the basis of the kinetic data a bimolecular mechanism, involving direct attack of the tin(II) halide on the nickel dimer, has been proposed. The thermal insertion with tin(II) bromide was found to proceed with an activation enthalpy of 19.4 ± 0.2 kcal/mol and an activation entropy of −8.8 ± 0.4 cal deg−1 mol−1. For the thermal insertion with tin(II) chloride a ΔH≠ and ΔS≠ of 22.5 ± 0.2 kcal/mol and −4.0 ± 0.2 cal deg−1 mol−1, respectively, were observed.

Nonlinear dynamics of pulsating detonation wave with two-stage chemical kinetics in the shock-attached frame

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yaroslava E. Poroshyna ◽  
Aleksander I. Lopato ◽  
Pavel S. Utkin
Keyword(s):  
Wave Propagation ◽  
Detonation Wave ◽  
Model Comparison ◽  
Approximation Order ◽  
Transition Regime ◽  
Stage Model ◽  
Two Stage ◽  
One Dimensional ◽  
Kinetics Of ◽  
Detonation Wave Propagation

Abstract The paper contributes to the clarification of the mechanism of one-dimensional pulsating detonation wave propagation for the transition regime with two-scale pulsations. For this purpose, a novel numerical algorithm has been developed for the numerical investigation of the gaseous pulsating detonation wave using the two-stage model of kinetics of chemical reactions in the shock-attached frame. The influence of grid resolution, approximation order and the type of rear boundary conditions on the solution has been studied for four main regimes of detonation wave propagation for this model. Comparison of dynamics of pulsations with results of other authors has been carried out.

scholarly journals The combustion of aromatic and alicyclic hydrocarbons. II. The ignition of aromatic hydrocarbons at high temperatures

1939 ◽  
Vol 171 (946) ◽  
pp. 421-433 ◽  
Keyword(s):  
High Temperatures ◽  
Aromatic Hydrocarbons ◽  
Isothermal Oxidation ◽  
Present Communication ◽  
Temperature Range ◽  
Benzene Toluene ◽  
The Subject ◽  
Kinetics Of

In the first paper of this series (Burgoyne 1937) the kinetics of the isothermal oxidation above 400° C of several aromatic hydrocarbons was studied. The present communication extends this work to include the phenomena of ignition in the same temperature range, whilst the corresponding reactions below 400° C form the subject of further investigations now in progress. The hydrocarbons at present under consideration are benzene, toluene, ethylbenzene, n -propylbenzene, o-, m - and p -xylenes and mesitylene.

Overall crystallization kinetics of polymorphic propylene–ethylene random copolymers: A two-stage parallel model of Avrami kinetics

Polymer ◽  
2007 ◽  
Vol 48 (11) ◽  
pp. 3170-3182 ◽  
Author(s):  
Y.L. Chiari ◽  
M. Vadlamudi ◽  
R. Chella ◽  
K. Jeon ◽  
R.G. Alamo
Keyword(s):  
Crystallization Kinetics ◽  
Random Copolymers ◽  
Parallel Model ◽  
Two Stage ◽  
Avrami Kinetics ◽  
Kinetics Of

scholarly journals Fast-Scanning Chip-Calorimetry Measurement of Crystallization Kinetics of Poly(Glycolic Acid)

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 891
Author(s):  
Yongxuan Chen ◽  
Kefeng Xie ◽  
Yucheng He ◽  
Wenbing Hu
Keyword(s):  
Crystallization Kinetics ◽  
Temperature Region ◽  
Glycolic Acid ◽  
Crystal Nucleation ◽  
Side Group ◽  
Half Time ◽  
Temperature Range ◽  
Chip Calorimetry ◽  
Kinetics Of ◽  
Fast Scanning Chip Calorimetry

We report fast-scanning chip-calorimetry measurement of isothermal crystallization kinetics of poly(glycolic acid) (PGA) in a broad temperature range. We observed that PGA crystallization could be suppressed by cooling rates beyond -100 K s−1 and, after fast cooling, by heating rates beyond 50 K s-1. In addition, the parabolic curve of crystallization half-time versus crystallization temperature shows that PGA crystallizes the fastest at 130 °C with the minimum crystallization half-time of 4.28 s. We compared our results to those of poly(L-lactic acid) (PLLA) with nearby molecular weights previously reported by Androsch et al. We found that PGA crystallizes generally more quickly than PLLA. In comparison to PLLA, PGA has a much smaller hydrogen side group than the methyl side group in PLLA; therefore, crystal nucleation is favored by the higher molecular mobility of PGA in the low temperature region as well as by the denser molecular packing of PGA in the high temperature region, and the two factors together decide the higher crystallization rates of PGA in the whole temperature range.

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