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On-Surface Synthesis of Unsaturated Hydrocarbon Chains through C-S Activation.

ABSTRACT: We use an on-surface synthesis approach to drive the homocoupling reaction of a simple dithiophenyl-functionalized precursor on Cu(111). The C-S activation reaction is initiated at low annealing temperature and yields unsaturated hydrocarbon chains interconnected in a fully conjugated reticulated network. High-resolution atomic force microscopy imaging reveals the opening of the thiophenyl rings and the presence of trans- and cis-oligoacetylene chains as well as pentalene units. The chemical transformations were studied by C 1s and S 2p core level photoemission spectroscopy and supported by theoretical calculations. At higher annealing temperature, additional cyclization reactions take place, leading to the formation of small graphene flakes.

SUBMITTER: Giovanelli L

PROVIDER: S-EPMC9540368 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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On-Surface Synthesis of Unsaturated Hydrocarbon Chains through C-S Activation.

Giovanelli Luca L Pawlak Rémy R Hussein Fatima F MacLean Oliver O Rosei Federico F Song Wentao W Pigot Corentin C Dumur Frédéric F Gigmes Didier D Ksari Younal Y Bondino Federica F Magnano Elena E Meyer Ernst E Clair Sylvain S

Chemistry (Weinheim an der Bergstrasse, Germany) 20220711 47

We use an on-surface synthesis approach to drive the homocoupling reaction of a simple dithiophenyl-functionalized precursor on Cu(111). The C-S activation reaction is initiated at low annealing temperature and yields unsaturated hydrocarbon chains interconnected in a fully conjugated reticulated network. High-resolution atomic force microscopy imaging reveals the opening of the thiophenyl rings and the presence of trans- and cis-oligoacetylene chains as well as pentalene units. The chemical tra ...[more]

PMID: 35657383

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