Docking in metal-organic frameworks.
The use of metal-organic frameworks (MOFs) so far has largely relied on nonspecific binding interactions to host small molecular guests. We used long organic struts (approximately 2 nanometers) incorporating 34- and 36-membered macrocyclic polyethers as recognition modules in the construction of several crystalline primitive cubic frameworks that engage in specific binding in a way not observed in passive, open reticulated geometries. MOF-1001 is capable of docking paraquat dication (PQT2+) guests within the macrocycles in a stereoelectronically controlled fashion. This act of specific complexation yields quantitatively the corresponding MOF-1001 pseudorotaxanes, as confirmed by x-ray diffraction and by solid- and solution-state nuclear magnetic resonance spectroscopic studies performed on MOF-1001, its pseudorotaxanes, and their molecular strut precursors. A control experiment involving the attempted inclusion of PQT2+ inside a framework (MOF-177) devoid of polyether struts showed negligible uptake of PQT2+, indicating the importance of the macrocyclic polyether in PQT2+ docking.
Li
Qiaowei
Q
Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA. qwli@chem.ucla.edu
Zhang
Wenyu
W
Miljanić
Ognjen S
OS
Sue
Chi-Hau
CH
Zhao
Yan-Li
YL
Liu
Lihua
L
Knobler
Carolyn B
CB
Stoddart
J Fraser
JF
Yaghi
Omar M
OM