Aromatic Substituent Effects on the Flexibility of Metal–Organic Frameworks

• Published in: Inorganic chemistry Vol. 55; no. 15; pp. 7576 - 7581
• Main Authors: Hahm, Hyungwoo, Yoo, Kwangho, Ha, Hyeonbin, Kim, Min
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 01-08-2016
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.6b00983

The flexibility (or breathing behavior) of zinc-based metal–organic frameworks (MOFs) has been manipulated by regioisomeric and positional control of organic functionalities. Ten new regioisomeric BDC (ortho- or para-disubstituted benzene-1,4-dicarboxylic acid) ligands have been synthesized and applied to a DMOF (dabco MOF) system, which has a zinc­(II) paddle-wheel SBU (secondary building unit). Among the new regioisomeric MOFs, the NH2–OMe combination showed significant flexibility (breathing behavior) changes by simply altering the functional group positions (from 2,3 to 2,5). The electronic density of the benzene ring was considered to be a major factor in the flexibility changes in the regioisomeric MOF system.