Room-Temperature Synthesis of Covalent Organic Frameworks with a Boronic Ester Linkage at the Liquid/Solid Interface

Chunhua Liu; Yanxia Yu; Wei Zhang; Qingdao Zeng; Shengbin Lei

doi:10.1002/chem.201603547

Room-Temperature Synthesis of Covalent Organic Frameworks with a Boronic Ester Linkage at the Liquid/Solid Interface

Chemistry. 2016 Dec 19;22(51):18412-18418. doi: 10.1002/chem.201603547. Epub 2016 Oct 27.

Authors

Chunhua Liu¹, Yanxia Yu¹, Wei Zhang², Qingdao Zeng³, Shengbin Lei^{1

4}

Affiliations

¹ State Key Laboratory of Robotics and System (HIT), Harbin Institute of Technology, Harbin, 150080, P. R. China.
² College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China.
³ CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology (NCNST), Beijing, 100190, P. R. China.
⁴ Department of Chemistry, School of Science and Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin, 300072, P. R. China.

PMID: 27709716
DOI: 10.1002/chem.201603547

Abstract

With various prospected applications in the field of nanoelectronics and catalysis, on-surface synthesis of single-layer covalent organic frameworks (surface COFs) with designable structures and properties have attracted enormous interest. Herein, we report on a scanning tunneling microscopic investigation of the surface-confined synthesis of a covalently bonded boronic ester network directly at the octanoic acid/ highly oriented pyrolytic graphite(HOPG) interface under room temperature. The dynamic reaction process was investigated in detail. STM results indicate that the surface networks undergo structural evolution from a hybrid covalent/noncovalent multiwall porous network to single-wall hexagonal COF with the decrease of monomer concentration. Further experimental observation disclosed that the boronic ester-linked system is sensitive to instantaneous voltage pulses and the stimulation of the STM tip. In addition, the ¹ H NMR spectra has further confirmed that the surface and octanoic acid may play important roles in promoting the reaction between 4,4'-phenylazobenzoyl diboronic acid (ABBA) and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) building units.

Keywords: boronic acid; covalent organic frameworks; polymers; scanning tunneling microscopy; solid/liquid interface.