Paper: Urea-Linked Covalent Organic Frameworks

Authors: C. Zhao, C. S. Diercks, C. Zhu, N. Hanikel, X. Pei, and O. M. Yaghi

Citation: J. Am. Chem. Soc.2018, 140, 16438-16441

DOI: 10.1021/jacs.8b10612

Abstract: 2D covalent organic frameworks (COFs) with flexible urea linkages have been synthesized by condensation of 1,3,5-triformylphloroglucinol (TFP) with 1,4-phenylenediurea (BDU) or 1,1'-(3,3'-dimethyl-[1,1'-biphenyl]-4,4'-diyl)diurea (DMBDU). The resulting COF-117 and COF-118 undergo reversible structural dynamics within their layers, in response to inclusion and removal of guest molecules, emanating from urea C–N bond rotation and interlayer hydrogen-bonding interactions. These compounds are the first urea-linked COFs, serving to expand the scope of reticular chemistry.