Co-reporter:Biao Yang;Haiping Lin;Kangjian Miao;Pan Zhu;Liangbo Liang;Kewei Sun;Dr. Haiming Zhang;Dr. Jian Fan; Vincent Meunier; Youyong Li;Dr. Qing Li; Lifeng Chi
Angewandte Chemie 2016 Volume 128( Issue 34) pp:10035-10039
Publication Date(Web):
DOI:10.1002/ange.201602414
Abstract
On-surface synthesis has prompted much interest in recent years because it provides an alternative strategy for controlling chemical reactions and allows for the direct observation of reaction pathways. Herein, we combined scanning tunneling microscopy and density functional theory to provide extensive evidence for the conversion of alkoxybenzene-containing ethers into alcohols by means of surface synthesis. The reported dealkylation reactions are finely controlled by the annealing parameters, which govern the onset of successive alkyl chains dissociations. Moreover, density functional theory calculations elucidate the details of the reaction pathways, showing that dealkylation reactions are surface-assisted and very different from their homogeneous analogues in solution.
Co-reporter:Zhongmiao Gong, Biao Yang, Haiping Lin, Yunyu Tang, Zeyuan Tang, Junjie Zhang, Haiming Zhang, Youyong Li, Yongshu Xie, Qing Li, and Lifeng Chi
ACS Nano 2016 Volume 10(Issue 4) pp:4228
Publication Date(Web):April 4, 2016
DOI:10.1021/acsnano.5b07601
Surface-supported coupling reactions between 1,3,5-tris(4-formylphenyl)benzene and aromatic amines have been investigated on Au(111) using scanning tunneling microscopy under ultra-high-vacuum conditions. Upon annealing to moderate temperatures, various products, involving the discrete oligomers and the surface covalent organic frameworks, are obtained through thermal-triggered on-surface chemical reactions. We conclude from the systematic experiments that the stoichiometric composition of the reactants is vital to the surface reaction products, which is rarely reported so far. With this knowledge, we have successfully prepared two-dimensional covalently bonded networks by optimizing the stoichiometric proportions of the reaction precursors.Keywords: aldehyde−amine coupling; on-surface chemistry; scanning tunneling microscopy; stoichiometric ratio; two-dimensional framework
Co-reporter:Biao Yang;Haiping Lin;Kangjian Miao;Pan Zhu;Liangbo Liang;Kewei Sun;Dr. Haiming Zhang;Dr. Jian Fan; Vincent Meunier; Youyong Li;Dr. Qing Li; Lifeng Chi
Angewandte Chemie International Edition 2016 Volume 55( Issue 34) pp:9881-9885
Publication Date(Web):
DOI:10.1002/anie.201602414
Abstract
On-surface synthesis has prompted much interest in recent years because it provides an alternative strategy for controlling chemical reactions and allows for the direct observation of reaction pathways. Herein, we combined scanning tunneling microscopy and density functional theory to provide extensive evidence for the conversion of alkoxybenzene-containing ethers into alcohols by means of surface synthesis. The reported dealkylation reactions are finely controlled by the annealing parameters, which govern the onset of successive alkyl chains dissociations. Moreover, density functional theory calculations elucidate the details of the reaction pathways, showing that dealkylation reactions are surface-assisted and very different from their homogeneous analogues in solution.
Co-reporter:Biao Yang; Jonas Björk; Haiping Lin; Xiaoqing Zhang; Haiming Zhang; Youyong Li; Jian Fan; Qing Li;Lifeng Chi
Journal of the American Chemical Society 2015 Volume 137(Issue 15) pp:4904-4907
Publication Date(Web):March 24, 2015
DOI:10.1021/jacs.5b00774
The formation of additional phenyl rings on surfaces is of particular interest because it allows for the building-up of surface covalent organic frameworks. In this work, we show for the first time that the cyclotrimerization of acetyls to aromatics provides a promising approach to 2D conjugated covalent networks on surfaces under ultrahigh vacuum. With the aid of scanning tunneling microscopy, we have systematically studied the reaction pathways and the products. With the combination of density functional theory calculations and X-ray photoemission spectroscopy, the surface-assisted reaction mechanism, which is different from that in solution, was explored.