Driving Forces for Covalent Assembly of Porphyrins by Selective C-H Bond Activation and Intermolecular Coupling on a Copper Surface

Floris, Andrea; Haq, Sam; Veld, Mendel In't; Amabilino, David A.; Raval, Rasmita; Kantorovich, Lev

Abstract

© 2016 American Chemical Society. Recent synthesis of covalent organic assemblies at surfaces has opened the promise of producing robust nanostructures for functional interfaces. To uncover how this new chemistry works at surfaces and understand the underlying mechanisms that control bond-breaking and bond-making processes at specific positions of the participating molecules, we study here the coupling reaction of tetra(mesityl)porphyrin molecules, which creates covalently connected networks on the Cu(110) surface by utilizing the 4-methyl groups as unique connection points. Using scanning tunneling microscopy (STM), state-of-The-Art density functional theory (DFT), and Nudged Elastic Band (NEB) calculations, we show that the unique directionality of the covalent bonding is found to stem from a chain of highly selective C-H activation and dehydrogenation processes, followed by specific intermolecular C-C coupling reactions that are facilitated by the surface, by steric constraints, and by anisotropic molecular diffusion. These insights provide the first steps toward developing synthetic rules for complex two-dimensional covalent organic chemistry that can be enacted directly at a surface to deliver specific macromolecular structures designed for specific functions.

Citation

Floris, A., Haq, S., Veld, M. I., Amabilino, D. A., Raval, R., & Kantorovich, L. (2016). Driving Forces for Covalent Assembly of Porphyrins by Selective C-H Bond Activation and Intermolecular Coupling on a Copper Surface. Journal of the American Chemical Society, 138(18), 5837-5847. https://doi.org/10.1021/jacs.5b11594

• Journal Article Type: Article
• Acceptance Date: Apr 19, 2016
• Online Publication Date: May 2, 2016
• Publication Date: May 11, 2016
• Deposit Date: Aug 25, 2016
• Publicly Available Date: Aug 25, 2016
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 138
• Issue: 18
• Pages: 5837-5847
• DOI: https://doi.org/10.1021/jacs.5b11594
• Public URL: https://nottingham-repository.worktribe.com/output/790442
• Publisher URL: http://pubs.acs.org/doi/abs/10.1021/jacs.5b11594
• Additional Information: This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/jacs.5b11594.
• Contract Date: Aug 25, 2016