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Intramolecular Coupling of Terminal Alkynes by Atom Manipulation.

ABSTRACT: Glaser-like coupling of terminal alkynes by thermal activation is extensively used in on-surface chemistry. Here we demonstrate an intramolecular version of this reaction performed by atom manipulation. We used voltage pulses from the tip to trigger a Glaser-like coupling between terminal alkyne carbons within a custom-synthesized precursor molecule adsorbed on bilayer NaCl on Cu(111). Different conformations of the precursor molecule and the product were characterized by molecular structure elucidation with atomic force microscopy and orbital density mapping with scanning tunneling microscopy, accompanied by density functional theory calculations. We revealed partially dehydrogenated intermediates, providing insight into the reaction pathway.

SUBMITTER: Albrecht F

PROVIDER: S-EPMC7756451 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Intramolecular Coupling of Terminal Alkynes by Atom Manipulation.

Albrecht Florian F Rey Dulce D Fatayer Shadi S Schulz Fabian F Pérez Dolores D Peña Diego D Gross Leo L

Angewandte Chemie (International ed. in English) 20201013 51

Glaser-like coupling of terminal alkynes by thermal activation is extensively used in on-surface chemistry. Here we demonstrate an intramolecular version of this reaction performed by atom manipulation. We used voltage pulses from the tip to trigger a Glaser-like coupling between terminal alkyne carbons within a custom-synthesized precursor molecule adsorbed on bilayer NaCl on Cu(111). Different conformations of the precursor molecule and the product were characterized by molecular structure elu ...[more]

PMID: 32845044

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