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Updated: Jul 7, 2026
11:13
Identification of Kinase-substrate Pairs Using High Throughput Screening
Published on: August 29, 2015
Insights into Sonogashira cross-coupling by high-throughput kinetics and descriptor modeling
Markus R an der Heiden1, Herbert Plenio, Stefan Immel
1Inorganic Chemistry, Zintl-Institute, Darmstadt University of Technology, Petersenstrasse 18, 64287 Darmstadt, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|February 22, 2008
Summary
This study introduces a high-throughput method for monitoring homogeneous catalysis, analyzing nearly 500 Sonogashira coupling reactions. It reveals insights into reaction kinetics and the factors influencing activation parameters for various aryl halides.
Area of Science:
- Homogeneous catalysis
- Reaction kinetics
- Organic synthesis
Background:
- High-throughput screening is crucial for optimizing catalytic reactions.
- Understanding reaction kinetics aids in catalyst design and process development.
- The Sonogashira reaction is a vital tool in organic synthesis for C-C bond formation.
Purpose of the Study:
- To develop and validate a high-throughput method for monitoring reaction kinetics in homogeneous catalysis.
- To analyze the kinetics of numerous Sonogashira coupling reactions.
- To investigate the influence of substrate structure and reaction conditions on catalytic efficiency.
Main Methods:
- A novel method enabling up to 25 coupling reactions in a single vessel.
- Systematic analysis of phenylacetylene with diverse aryl bromides and palladium-phosphine complexes.
- Temperature-dependent kinetic studies of various aryl halides (ArX) using Eyring plots.
Main Results:
- Kinetics of nearly 500 Sonogashira coupling reactions were analyzed.
- Activation enthalpies and entropies were determined for aryl chlorides, bromides, and iodides.
- Density Functional Theory (DFT) calculations showed a correlation between activation enthalpy and aryl halide HOMO energies, identifying them in the rate-limiting step.
Conclusions:
- The developed method allows for efficient, high-throughput kinetic analysis of homogeneous catalysis.
- Activation parameters for Sonogashira reactions vary significantly with aryl halide type (Cl, Br, I).
- DFT calculations confirm the role of aryl halides in the rate-determining step, correlating with their electronic properties.
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