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Azo bond formation on metal surfaces.

ABSTRACT: The formation of azo compounds via redox cross-coupling of nitroarenes and arylamines, challenging in solution phase chemistry, is achieved by on-surface chemistry. Reaction products are analyzed with a cryogenic scanning tunneling microscope (STM) and X-ray photoelectron spectroscopy (XPS). By using well-designed precursors containing both an amino and a nitro functionality, azo polymers are prepared on surface via highly efficient nitro-amino cross-coupling. Experiments conducted on other substrates and surface orientations reveal that the metal surface has a significant effect on the reaction efficiency. The reaction was further found to proceed from partially oxidized/reduced precursors in dimerization reactions, shedding light on the mechanism that was studied by DFT calculations.

SUBMITTER: Meng X

PROVIDER: S-EPMC7839811 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Azo bond formation on metal surfaces.

Meng Xiangzhi X Klaasen Henning H Viergutz Lena L Schulze Lammers Bertram B Witteler Melanie C MC Mönig Harry H Amirjalayer Saeed S Liu Lacheng L Neugebauer Johannes J Gao Hong-Ying HY Studer Armido A Fuchs Harald H

Angewandte Chemie (International ed. in English) 20201211 3

The formation of azo compounds via redox cross-coupling of nitroarenes and arylamines, challenging in solution phase chemistry, is achieved by on-surface chemistry. Reaction products are analyzed with a cryogenic scanning tunneling microscope (STM) and X-ray photoelectron spectroscopy (XPS). By using well-designed precursors containing both an amino and a nitro functionality, azo polymers are prepared on surface via highly efficient nitro-amino cross-coupling. Experiments conducted on other subs ...[more]

PMID: 33197115

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