Xiong Zhou, Chenguang Wang, Yajie Zhang, Fang Cheng, Yang He, Qian Shen, Jian Shang, Xiang Shao,* Wei Ji,* Wei Chen, Guoqin Xu, Kai Wu*
1SKLSCUSS, BNLMS, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
2Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100872, China.
3Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China.
4Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
5SPURc, 1 CREATE Way, #15-01, CREATE Tower, Singapore 138602, Singapore.
6Department of Physics and Astronomy, Collaborative Innovation Center of Advanced Microstructures, Shanghai Jiao Tong University, Shanghai 200240, China.
DOI:10.1002/anie.201705018 Publication Date: 18 August 2017
Ullmann coupling of 4-bromobiphenyl by thermally catalyzed on Ag(111), Cu(111) and Cu(100) surfaces was scrutinized by scanning tunneling microscopy as well as theoretical calculations. Detailed experimental evidence showed that whether the initially formed organometallic intermediate self-assembled or sparsely dispersed at surfaces essentially determined its subsequent reaction pathways. In specific, the assembled organometallic intermediates at full coverage underwent a single-barrier process to directly convert into the final coupling products while the sparsely dispersed ones at low coverage went through a double-barrier process via newly identified clover-shaped intermediates prior to their formation of the final coupling products. This demonstrates that the self-assembly strategy can efficiently steer surface reaction pathways and dynamics.