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Coordination-Controlled C-C Coupling Products via ortho-Site C-H Activation.

ABSTRACT: The coordination-restricted ortho-site C-H bond activation and dehydrogenative homocoupling of 4,4'-(1,3-phenylene)dipyridine (1,3-BPyB) and 4,4'-(1,4-phenylene)dipyridine (1,4-BPyB) on different metal surfaces were studied by a combination of scanning tunneling microscopy, noncontact atomic force microscopy, and density functional theory calculations. The coupling products on Cu(111) exhibited certain configurations subject to the spatial restriction of robust two-fold Cu-N coordination bonds. Compared to the V-shaped 1,3-BPyB, the straight backbone of 1,4-BPyB helped to further reduce the variety of reactive products. By utilizing the three-fold coordination of Fe atoms with 1,4-BPyB molecules on Au(111), a large-scale network containing single products was constructed. Our results offer a promising protocol for controllable on-surface synthesis with the aid of robust coordination interactions.

SUBMITTER: Zhang X

PROVIDER: S-EPMC6396320 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Coordination-Controlled C-C Coupling Products via ortho-Site C-H Activation.

Zhang Xue X Xue Na N Li Chao C Li Na N Wang Hao H Kocić Nemanja N Beniwal Sumit S Palotás Krisztián K Li Ruoning R Xue Qiang Q Maier Sabine S Hou Shimin S Wang Yongfeng Y

ACS nano 20190211 2

The coordination-restricted ortho-site C-H bond activation and dehydrogenative homocoupling of 4,4'-(1,3-phenylene)dipyridine (1,3-BPyB) and 4,4'-(1,4-phenylene)dipyridine (1,4-BPyB) on different metal surfaces were studied by a combination of scanning tunneling microscopy, noncontact atomic force microscopy, and density functional theory calculations. The coupling products on Cu(111) exhibited certain configurations subject to the spatial restriction of robust two-fold Cu-N coordination bonds. ...[more]

PMID: 30726665

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