Guidance on surface cyclization reactions through coordination structures
Qing Wang1, Xiaoqing Liu1, Tianming Lu1
1Department of Physics, Nanchang University, Nanchang 330031, People's Republic of China.
The Journal of Chemical Physics
|December 3, 2024
Summary
Metal coordination structures influence chemical reactions. On gold surfaces, 2,3-dibromo-6,7-dicyanonaphthalene (DDN) forms diverse products due to overlapping reaction temperatures, while on silver, it yields a single polymer via metal-induced cyclization.
Area of Science:
- Surface science
- Organic chemistry
- Materials science
Background:
- Metal coordination structures are key to reaction pathways and products.
- 2,3-dibromo-6,7-dicyanonaphthalene (DDN) possesses cyano and halogen functional groups.
Purpose of the Study:
- Investigate the role of metal surfaces in regulating the reactivity of DDN.
- Explore the formation of cyclization and polymerization products on different metal substrates.
Main Methods:
- Scanning tunneling microscopy (STM) was used to study DDN on Au(111) and Ag(111) surfaces at room temperature.
- Analysis of molecular self-assembly and reaction pathways on distinct metallic substrates.
Main Results:
- On Au(111), overlapping reaction temperatures of bromine and cyano groups in DDN led to diverse C-C coupling and cyclization products.
- On Ag(111), metal-coordinated structures directly induced a single type of polymer formation through cyclization.
Conclusions:
- The interplay between metal coordination structures and the activation temperatures of functional groups dictates polymerization outcomes.
- Surface-dependent reactivity of DDN highlights the importance of substrate interactions in controlling molecular transformations.
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