Premium
Two Robust Porous Metal–Organic Frameworks Sustained by Distinct Catenation: Selective Gas Sorption and Single‐Crystal‐to‐Single‐Crystal Guest Exchange
Author(s) -
Yang Rui,
Li Lei,
Xiong Ying,
Li JianRong,
Zhou HongCai,
Su ChengYong
Publication year - 2010
Publication title -
chemistry – an asian journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.18
H-Index - 106
eISSN - 1861-471X
pISSN - 1861-4728
DOI - 10.1002/asia.201000218
Subject(s) - single crystal , metal organic framework , powder diffraction , crystallography , catenation , adsorption , sorption , molecule , chemistry , benzene , solvent , thermogravimetry , materials science , inorganic chemistry , organic chemistry , dna , biochemistry
Assembly of copper(I) halide with a new tripodal ligand, benzene‐1,3,5‐triyl triisonicotinate (BTTP4), afforded two porous metal–organic frameworks, [Cu 2 I 2 (BTTP4)]⊃2 CH 3 CN ( 1⋅ 2 CH 3 CN) and [CuBr(BTTP4)]⊃(CH 3 CN ⋅ CHCl 3 ⋅ H 2 O) ( 2⋅ solvents), which have been characterized by IR spectroscopy, thermogravimetry (TG), single‐crystal, and powder X‐ray diffraction (PXRD) methods. Compound 1.CH3CN is a polycatenated 3D framework that consists of 2D (6,3) networks through inclined catenation, whereas 2 is a doubly interpenetrated 3D framework possessing the ThSi 2 ‐type ( ths ) (10,3)‐ b topology. Both frameworks contain 1D channels of effective sizes 9×12 and 10×10 Å 2 , which amounts to 43 and 40 % space volume accessible for solvent molecules, respectively. The TG and variable‐temperature PXRD studies indicated that the frameworks can be completely evacuated while retaining the permanent porosity, which was further verified by measurement of the desolvated complex [Cu 2 I 2 (BTTP4)] ( 1′ ). The subsequent guest‐exchange study on the solvent‐free framework revealed that various solvent molecules can be adsorbed through a single‐crystal‐to‐single‐crystal manner, thus giving rise to the guest‐captured structures [Cu 2 I 2 (BTTP4)]⊃C 6 H 6 ( 1.benzene ), [Cu 2 I 2 (BTTP4)]⊃2 C 7 H 8 ( 1.2toluene ), and [Cu 2 I 2 (BTTP4)]⊃2 C 8 H 10 ( 1.2ethyl benzene ). The gas‐adsorption investigation disclosed that two kinds of frameworks exhibited comparable CO 2 storage capacity (86–111 mL g −1 at 1 atm) but nearly none for N 2 and H 2 , thereby implying its separation ability of CO 2 over N 2 and H 2 . The vapor‐adsorption study revealed the preferential inclusion of aromatic guests over nonaromatic solvents by the empty framework, which is indicative of selectivity toward benzene over cyclohexane.