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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 |

REPOSITORIES: biostudies-literature

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Correction to "From Hexaphenylbenzene to 1,2,3,4,5,6-Hexacyclohexylcyclohexane".

Project description: Not available

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