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Polymerization or cyclic dimerization: solvent dependent homo-coupling of terminal alkynes at HOPG surface.

ABSTRACT: Surface reactivity has become one of the most important issues in surface chemistry over the past few years. In this work, we, for the first time, have investigated the homo-coupling of a special terminal alkyne derivative on the highly oriented pyrolitic graphite (HOPG) surface. Using scanning tunneling microscopy (STM) technique, we have found that such coupling reaction seriously depends on the supramolecular assembly of the monomer on the studied substrate, whereas the latter appears an obvious solvent effect. As a result, the reaction in our system undergoes polymerization and cyclic dimerization process in 1-phenyloctane and 1,2,4-trichlorobenzene, respectively. That is to say, the solvent effect can be extended from the two-dimensional (2D) supramolecular self-assembly to surface chemical reactions, and the selective homo-coupling has been successfully achieved at the solid/liquid interface.

SUBMITTER: Zhang X

PROVIDER: S-EPMC3904147 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Polymerization or cyclic dimerization: solvent dependent homo-coupling of terminal alkynes at HOPG surface.

Zhang Xuemei X Liao Lingyan L Wang Shuai S Hu Fangyun F Wang Chen C Zeng Qingdao Q

Scientific reports 20140128

Surface reactivity has become one of the most important issues in surface chemistry over the past few years. In this work, we, for the first time, have investigated the homo-coupling of a special terminal alkyne derivative on the highly oriented pyrolitic graphite (HOPG) surface. Using scanning tunneling microscopy (STM) technique, we have found that such coupling reaction seriously depends on the supramolecular assembly of the monomer on the studied substrate, whereas the latter appears an obvi ...[more]

PMID: 24469357

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