scholarly journals Mechanistic studies of a “Declick” reaction

2019 ◽  
Vol 10 (38) ◽  
pp. 8817-8824 ◽  
Author(s):  
Margaret K. Meadows ◽  
Xiaolong Sun ◽  
Igor V. Kolesnichenko ◽  
Caroline M. Hinson ◽  
Kenneth A. Johnson ◽  
...  
Keyword(s):  
Kinetic Analysis ◽  
Mechanistic Studies ◽  
Step Mechanism

Detailed kinetic analysis reveals a complex multi-step mechanism for an amine-thiol “declick” reaction.

scholarly journals Operando Infrared (IR) Coupled to Steady-State Isotopic Transient Kinetic Analysis (SSITKA) for Photocatalysis: Reactivity and Mechanistic Studies

ACS Catalysis ◽  
2013 ◽  
Vol 3 (12) ◽  
pp. 2790-2798 ◽  
Author(s):  
Mohamad El-Roz ◽  
Philippe Bazin ◽  
Marco Daturi ◽  
Frederic Thibault-Starzyk
Keyword(s):  
Steady State ◽  
Kinetic Analysis ◽  
Mechanistic Studies ◽  
Isotopic Transient Kinetic Analysis

scholarly journals Mechanistic Studies of Pd(II)-Catalyzed E/Z Isomerization of Unactivated Alkenes: Evidence for a Monometallic Nucleopalladation Pathway

2020 ◽  
Author(s):  
Rei Matsuura ◽  
Malkanthi Karunananda ◽  
Mingyu Liu ◽  
Nhi Nguyen ◽  
Donna Blackmond ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Kinetic Analysis ◽  
Kinetic Modeling ◽  
Spectroscopic Studies ◽  
Mechanistic Studies ◽  
Common Process ◽  
Directing Group

Pd(II)-catalyzed <i>E</i>/<i>Z</i> isomerization of alkenes is a common process—yet is largely uncharacterized, particularly with non-conjugated alkenes. In this work, the mechanism of Pd(II)-catalyzed <i>E</i>/<i>Z</i> isomerization of unactivated olefins containing an aminoquinoline-based amide directing group is probed using <i>in situ</i> kinetic analysis, spectroscopic studies, kinetic modeling, and DFT calculations. The directing group allows for stabilization and monitoring of previously undetectable intermediates. Collectively, the data are consistent with isomerization occurring through a monometallic nucleopalladation mechanism.

scholarly journals Mechanistic Studies of Pd(II)-Catalyzed E/Z Isomerization of Unactivated Alkenes: Evidence for a Monometallic Nucleopalladation Pathway

2020 ◽  
Author(s):  
Rei Matsuura ◽  
Malkanthi Karunananda ◽  
Mingyu Liu ◽  
Nhi Nguyen ◽  
Donna Blackmond ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Kinetic Analysis ◽  
Kinetic Modeling ◽  
Spectroscopic Studies ◽  
Mechanistic Studies ◽  
Common Process ◽  
Directing Group

Pd(II)-catalyzed <i>E</i>/<i>Z</i> isomerization of alkenes is a common process—yet is largely uncharacterized, particularly with non-conjugated alkenes. In this work, the mechanism of Pd(II)-catalyzed <i>E</i>/<i>Z</i> isomerization of unactivated olefins containing an aminoquinoline-based amide directing group is probed using <i>in situ</i> kinetic analysis, spectroscopic studies, kinetic modeling, and DFT calculations. The directing group allows for stabilization and monitoring of previously undetectable intermediates. Collectively, the data are consistent with isomerization occurring through a monometallic nucleopalladation mechanism.

scholarly journals Relevance of Particle Size Distribution to Kinetic Analysis: The Case of Thermal Dehydroxylation of Kaolinite

Processes ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1852
Author(s):  
Juan Arcenegui-Troya ◽  
Pedro E. Sánchez-Jiménez ◽  
Antonio Perejón ◽  
Luis A. Pérez-Maqueda
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Kinetic Analysis ◽  
Size Distribution ◽  
Kinetic Models ◽  
Solid State Reactions ◽  
Intermediate Species ◽  
Real Samples ◽  
The Common ◽  
Step Mechanism

Kinetic models used for the kinetic analysis of solid-state reactions assume ideal conditions that are very rarely fulfilled by real processes. One of the assumptions of these ideal models is that all sample particles have an identical size, while most real samples have an inherent particle size distribution (PSD). In this study, the influence of particle size distribution, including bimodal PSD, in kinetic analysis is investigated. Thus, it is observed that PSD can mislead the identification of the kinetic model followed by the reaction and even induce complex thermoanalytical curves that could be misinterpreted in terms of complex kinetics or intermediate species. For instance, in the case of a bimodal PSD, kinetics is affected up to the point that the process resembles a reaction driven by a multi-step mechanism. A procedure for considering the PSD in the kinetic analysis is presented and evaluated experimentally by studying the thermal dehydroxylation of kaolinite. This process, which does not fit any of the common ideal kinetic models proposed in the literature, was analyzed considering PSD influence. However, when PSD is taken into account, the process can be successfully described by a 3-D diffusion model (Jander’s equation). Therefore, it is concluded that the deviations from ideal models for this dehydroxylation process could be explained in terms of PSD.

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