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Structure Formation and Coupling Reactions of Hexaphenylbenzene and Its Brominated Analog.

ABSTRACT: The on-surface coupling of the prototypical precursor molecule for graphene nanoribbon synthesis, 6,11-dibromo-1,2,3,4-tetraphenyltriphenylene (C₄₂ Br₂ H₂₆ , TPTP), and its non-brominated analog hexaphenylbenzene (C₄₂ H₃₀ , HPB), was investigated on coinage metal substrates as a function of thermal treatment. For HPB, which forms non-covalent 2D monolayers at room temperature, a thermally induced transition of the monolayer's structure could be achieved by moderate annealing, which is likely driven by π-bond formation. It is found that the dibrominated carbon positions of TPTP do not guide the coupling if the growth occurs on a substrate at temperatures that are sufficient to initiate C-H bond activation. Instead, similar one-dimensional molecular structures are obtained for both types of precursors, HPB and TPTP.

SUBMITTER: Teeter JD

PROVIDER: S-EPMC8456788 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Structure Formation and Coupling Reactions of Hexaphenylbenzene and Its Brominated Analog.

Teeter Jacob D JD Costa Paulo S PS Dobner Christoph C Sarker Mamun M Sinitskii Alexander A Enders Axel A

Chemphyschem : a European journal of chemical physics and physical chemistry 20210718 17

The on-surface coupling of the prototypical precursor molecule for graphene nanoribbon synthesis, 6,11-dibromo-1,2,3,4-tetraphenyltriphenylene (C42 Br2 H26 , TPTP), and its non-brominated analog hexaphenylbenzene (C42 H30 , HPB), was investigated on coinage metal substrates as a function of thermal treatment. For HPB, which forms non-covalent 2D monolayers at room temperature, a thermally induced transition of the monolayer's structure could ...[more]

PMID: 33905148

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