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Carbon-Carbon Coupling on Inert Surfaces by Deposition of En?Route Generated Aryl Radicals.

ABSTRACT: To facilitate C-C coupling in on-surface synthesis on inert surfaces, we devised a radical deposition source (RDS) for the direct deposition of aryl radicals onto arbitrary substrates. Its core piece is a heated reactive drift tube through which halogenated precursors are deposited and en?route converted into radicals. For the proof of concept we study 4,4''-diiodo-p-terphenyl (DITP) precursors on iodine-passivated metal surfaces. Deposition with the RDS at room temperature results in highly regular structures comprised of mostly monomeric (terphenyl) or dimeric (sexiphenyl) biradicals. Mild heating activates progressive C-C coupling into more extended molecular wires. These structures are distinctly different from the self-assemblies observed upon conventional deposition of intact DITP. Direct deposition of radicals renders substrate reactivity unnecessary, thereby paving the road for synthesis on application-relevant inert surfaces.

SUBMITTER: Galeotti G

PROVIDER: S-EPMC7814669 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Carbon-Carbon Coupling on Inert Surfaces by Deposition of En Route Generated Aryl Radicals.

Galeotti Gianluca G Fritton Massimo M Lackinger Markus M

Angewandte Chemie (International ed. in English) 20201029 50

To facilitate C-C coupling in on-surface synthesis on inert surfaces, we devised a radical deposition source (RDS) for the direct deposition of aryl radicals onto arbitrary substrates. Its core piece is a heated reactive drift tube through which halogenated precursors are deposited and en route converted into radicals. For the proof of concept we study 4,4''-diiodo-p-terphenyl (DITP) precursors on iodine-passivated metal surfaces. Deposition with the RDS at room temperature results in highly reg ...[more]

PMID: 32926497

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