High‐Yield Synthesis of Pyridyl Conjugated Microporous Polymer Networks with Large Surface Areas: From Molecular Iodine Capture to Metal‐Free Heterogeneous Catalysis

Abstract

Capturing volatile radioactive nuclides including iodine (I129 or I131) is one of the major problems to be solved for environmental sustainability. Multiple types of functional microporous materials such as metal organic frameworks and covalent organic frameworks have been constructed for iodine emission control. However, most of the microporous materials are limited by their weak binding force with iodine and low stability, leading to low capture efficiencies. Herein, the synthesis of pyridyl conjugated microporous polymer networks with large surface areas (PCMP‐Y) up to 1304 m2 g−1 and high yields up to 95% via a simple Yamamoto cross‐coupling reaction, is reported. The PCMP‐Y carries amine and pyridine N groups which have stronger interactions with iodine molecules. The high specific surface areas and porosities of PCMP‐Y facilitate iodine capture, delivering a maximum adsorption capacity of 4.75 g g−1 in a short time (3 h), which is superior to a majority of porous materials reported. Moreover, the reversible desorption nature of PCMP‐Y capturing iodine imparts a platform for metal‐free heterogeneous catalyst, which can be applied to synthesize aminobenzothiazole medicines via O2‐promoted cascade reactions.

Transition-Metal-Free Synthesis of Conjugated Microporous Polymers via Amine-Catalyzed Suzuki-Miyaura Coupling Reaction

“…Representative classical transition-metal-catalysis C-C coupling reactions have been widely adopted for construction of CMPs, such as Suzuki-Miyaura coupling of an aryl-boron monomers with aryl halides; [7][8][9][10][11] Sonogashira-Hagihara cross coupling of aryl halides with alkynes; 6,[12][13][14][15] Buchwald-Hartwig coupling of aryl bromides with arylamines; [16][17] and Yamamoto homocoupling of aryl halides. [18][19][20] These methods either exploited expensive metal species or ligands, which made them neither economically nor environmentally favourable, precluding the potential large-scale production. Although previously we reported the KI promoted bromoacetylene self-coupling reaction to achieve the transition-metal free synthesis of CMPs, the monomers are complex for synthesizing and not rich in sources.…”

Triptycene-based and imine linked porous uniform microspheres for efficient and reversible scavenging of iodine from various media: a systematic study

“…Here, the two split peaks are assigned to the 3d 3/2 and 3d 5/2 energy levels of iodine centered at 630.73 and 619.28, respectively. 25,47,48,50,[72][73][74] The appearance of a shoulder in each individual split peak indicated the presence of polyiodide species (I 3 À and I 5 À ) along with molecular iodine (I 2 ). 70,71 Furthermore, it was observed (Fig.…”

Review of recent developments in iodine wasteform production

“…Alumina-based substrates for radionuclide capture have been under development for decades (e.g., Clariant AC-6120) with recent work showing promise for both aqueous capture and gas phase capture (Daryl Haefner, 2007;Wang and Chu, 2018;Zuo et al, 2020;Alsalbokh et al, 2021;Muhire et al, 2021). The investigation of AgI-containing alumina wasteforms has been well established with the use of HIP with these wasteforms being previously demonstrated (Tanabe et al, 2010).…”