NCAFM2023 Programme Booklet

Wednesday 0900 - 0920

ON-SURFACE REACTIONS TO FORM C-C BONDS

Pei-Nian Liu*

Key Laboratory for Advanced Materials, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China. Email: liupn@ecust.edu.cn

Bottom-up covalent assembly of molecular building blocks on surfaces by C-C cross coupling reactions is of great interesting for its potential in preparation the covalent architectures. For example, [3]Radialenes are the smallest carbocyclic structures with unusual topologies and cross-conjugated π-electronic structures. Here, we report a novel [1+1+1] cycloaddition reaction for the synthesis of aza[3]radialenes on the Ag(111) surface, where the steric hindrance of the chlorine substituents guides the selective and orientational assembling of the isocyanide precursors. By combining scanning tunneling microscopy, non-contact atomic force microscopy, and time-of-flight secondary ion mass spectrometry, we determined the atomic structure of the produced aza[3]radialenes. Further, two reaction pathways including synergistic and stepwise are proposed based on density functional theory calculations, which reveal the role of the chlorine substituents in the activation of the isocyano groups via electrostatic interaction.[1] In addition, the related on-surface coupling reactions of the isocyano groups will be presented. [2]

Fig. On-surface synthesis of [3]radialenes via [1+1+1] cycloaddition

References [1] D.-Y. Li, Y. Wang, X.-Y. Hou, Y.-T. Ren, L.-X. Kang, F.-H. Xue, Y.-C. Zhu, J.-W. Liu, M. Liu, X.-Q. Shi, X. Qiu, P.-N. Liu. Angew. Chem. Int. Ed. 2022, 61 , e202117714. [2] (a) D.-Y. Li, S.-W. Li, Y.-L. Xie, X. Hua, Y.-T. Long, A. Wang, P.-N. Liu, Nat. Commun. 2019, 10 , 2414. (b) D.-Y. Li, Y.-C. Zhu, S.-W. Li, C.-H. Shu, P.-N. Liu, Angew. Chem. Int. Ed. 2021, 60 , 11370.

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