Mechanochemical synthesis of pillar[5]quinone derived multi-microporous organic polymers for radioactive organic iodide capture and storage

Abstract

The incorporation of supramolecular macrocycles into porous organic polymers may endow the material with enhanced uptake of specific guests through host−guest interactions. Here we report a solvent and catalyst-free mechanochemical synthesis of pillar[5]quinone (P5Q) derived multi-microporous organic polymers with hydrophenazine linkages (MHP-P5Q), which show a unique 3-step N 2 adsorption isotherm. In comparison with analogous microporous hydrophenazine-linked organic polymers (MHPs) obtained using simple twofold benzoquinones, MHP-P5Q is demonstrated to have a superior performance in radioactive iodomethane (CH 3 I) capture and storage. Mechanistic studies show that the rigid pillar[5]arene cavity has additional binding sites though host−guest interactions as well as the halogen bond (−I⋯N = C−) and chemical adsorption in the multi-microporous MHP-P5Q mainly account for the rapid and highcapacity adsorption and long-term storage of CH 3 I.

Cationic Nonporous Macrocyclic Organic Compounds for Multimedia Iodine Capture

“…[9][10][11] Iodine capture materials not only should have good chemical and thermal stability, [12] but also have selectivity and durability for radioactive iodine. [13] Up to now, different kinds of porous materials have been used for gas absorption, guest molecules and I 2 capture, such as metal-organic frameworks (MOFs), [14][15][16][17][18] covalent organic frameworks (COFs), [19,20] supramolecular organic frameworks (SOFs), [21][22][23] porous organic cages, [24] and porous organic polymers. [2,25,26] Most of the porous iodine adsorption materials have the advantage of high adsorption capacity.…”

Asynchronous Double Schiff Base Formation of Pyrazole Porous Polymers for Selective Pd Recovery

“…To verify whether syn or anti addition is prevalent in the COP-214 formation, we have designed and synthesized a model compound starting from a 1-phenylbutane-1,3-dione (5) and naphthalene di-hydrazine (4) under reflux conditions in ethanol. In order to get further structural insights into the model monomer, a series of spectroscopic techniques ( 1 H NMR, 13 C NMR, 2D 1 H nuclear Overhauser effect (NOESY), 1D 1 H nuclear Overhauser effect (NOE), and LC-MASS) were carried out. NOESY NMR spectra show correlation signals between aromatic moieties due to close proximity, but no cross peak was observed between the methyl group and aromatic units (Figure S7a, Supporting Information).…”

“…A closer examination highlighted some unique pyrazole peaks at 1682 cm −1 (C=N stretching), 789 cm −1 (C=N out of plane) along with other characterized signals around 3046 and 2947 cm −1 (aromatic C-H stretching) (not clearly visible due to the stacking of three spectra), 1598 cm −1 (aromatic C=C stretching), 830 cm −1 (aromatic C-H out of plane), 1429 cm −1 (CH 3 stretching), 1017 cm −1 (CH 3 rocking), and 992 cm −1 (C-CH 3 bending) (Figure 3a). The molecular connectivity of COP-214 was elucidated by solid-state CP/MAS 13 C NMR spectroscopy. The CP/MAS 13 C NMR spectra of COP-214 were found to be in perfect agreement with that of the model structure (Figure S9, Supporting Information).…”

“…The molecular connectivity of COP-214 was elucidated by solid-state CP/MAS 13 C NMR spectroscopy. The CP/MAS 13 C NMR spectra of COP-214 were found to be in perfect agreement with that of the model structure (Figure S9, Supporting Information). In particular, the carbon atom of the -C=CH and -CH 3 of the acetylacetonate unit which resonated at 13.7 and 106.5 ppm, shows evidence of the presence of an acetylacetonate fragment.…”

Ternary Cocrystals with Large Soft Cavities: A 1,4‐diiodotetrafluorobenzene (DITFB)⋅4‐Biphenylpyridine N‐oxide (BPNO) Host Assembled by Inclusion of Planar Aromatic Guests

“…[9][10][11] Such hosts include metal-organic, covalent-organic, hydrogen-bonded organic, and halogenbonded organic frameworks, as well as porous organic polymers and inclusion crystals. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] Among the aforementioned noncovalent interactions, σ-hole and π-hole bonds are excellent supramolecular interactions owing to their high directionality, tunable binding strength, and hydrophobicity. [32][33][34][35][36][37][38][39][40][41] Due to the lack of flexibility and applicability of rigid cavities, recent efforts have been made to construct soft or flexible host cavities using σ-hole and π-hole bonds.…”