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Covalent anchoring of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) on the scaffold of conjugated microporous polymers (CMPs) was achieved via cost-effective FeCl3-catalyzed oxidative polymerization of dicarbazole functionalized TEMPO. These TEMPO-CMPs exhibit excellent catalytic performance for the aerobic oxidation of a wide variety of alcohols under metal-free conditions. In addition, the TEMPO-CMPs could be recycled at least 20 times with good retention of high catalytic activities.

Understanding of the binding characteristics of wetland dissolved organic matter (DOM) and different metals is important for the quantitative assessment of the environmental behavior of metals in wetlands. In this study, different types of spectroscopy including ultraviolet-visible absorption, Fourier transform infrared, and fluorescence spectroscopy was used to investigate the binding characteristics of Fe3+, Cu2+, Cr3+, Cd2+, and Zn2+ with DOM from wetland water. Differential absorption spectra identified binding sites for these five metals in this wetland DOM at 210 nm, 280 nm, 335 nm, and > 400 nm regions. The low binding capacity of DOM in this wetland with Cd and Zn indicated that the toxicity and environmental effects of these metals in this wetland warrant further study. The calculated △EEM combined with fluorescence regional integration (FRI) analysis clearly revealed that Fe and Cu preferred to bind with humic-like DOM while Cd and Zn preferred to bind with protein-like DOM in this wetland. △EEM successfully demonstrated the characteristics of DOM complexing with different metals and could be a compelling tool in evaluating metal-DOM interactions. In addition, 2D-FTIR-COS identified the binding sites and the dynamic processes of binding at the functional group level. Metals preferentially bind with the C O, C O functional group, and then binds to the O H functional group. This study revealed that different DOM components will facilitate the migration of different metals in the environment and provided new slights into an improved understanding of migration and transformation of metals in aquatic environments.

Under iodine-catalyzed and visible light-irradiated aerobic conditions, selenoalkoxylation of olefins with diselenides and alcohols can be efficiently achieved to afford the useful α -alkoxyl selenides in the presence of only 0.5 equiv. of H2O2. Controlling the sub-stoichiometric H2O2 amount is crucial to avoid the non-selective over-oxidation of the diselenides that leads to the ineffective hyper-valent selenium compounds. Meanwhile, under visible light irradiation, the green, safe, and low-cost air can work as a supplemental mild oxidant in the reaction to ensure selective oxidation of the diselenides, full conversion of the reactants, and ultimately good yield of the products.

Herein, we report two novel Anderson-type polyoxometalate (POM) built-in conjugated microporous polymers (CMPs), Bn-Anderson-CMP and Th-Anderson-CMP prepared through Sonogashira–Hagihara cross-coupling of tetrabromo-bifunctionalized Anderson-type POMs and 1,3,5-triethynylbenzene. These two Anderson-CMPs exhibit outstanding heterogeneous photocatalytic activities towards degrading organic dyes in water. Control photocatalysis experiments with different radical scavengers demonstrate that hydrogen peroxide and singlet oxygen are the primary active catalytic species. Moreover, these two CMPs can be easily recycled at least five times without a noticeable decrease in photocatalytic performances.

The discovery of a series of novel organic reactions has made methylenecyclopropanes (MCPs) some of the most popular building blocks in synthetic organic chemistry during the past two decades. Among reported works, the construction of heterocycles from MCPs has highlighted new synthetic methodologies that afford more opportunities for the quick synthesis of elaborately substituted products, and this should draw a great deal of attention. However, reviews in this area are insufficient, and the latest monograph on heterocycle synthesis from MCPs was published 12 years ago. This review aims to summarize the novel organic reactions of MCPs to produce heterocycles published in recent years, which have provided specific and powerful tools for organic synthesis.

A new ion-imprinted poly(ethyleneimine)(PEI)-functionalized silica sorbents were synthesized by a hydrothermal-assisted surface grafting technique with Pb(II) as the template, PEI as the functional molecular, and epichlorohydrin as the cross-linking agent for the selective adsorption of Pb(II) from aqueous solution, and was characterized by FTIR, SEM, TGA-DTA, nitrogen adsorption, and the static batch experiment. Static adsorption experiment results showed that Pb(II)-imprinted PEI-functionalized silica sorbents had high static adsorption capacity of 60.4 mg g−1, reached an equilibrium state within 20 min, displayed stable adsorption ability for Pb(II) ions in the range of pH 4–8, had satisfactory selectivity toward Pb(II) and could be used repeatedly. Compared with Freundlich and Dubinin–Radushkevich isotherms, equilibrium data fitted to Langmuir adsorption model. The kinetic process of adsorption followed a pseudo-second-order model compared to pseudo-first-order, Elovich and intraparticle diffu...

The discovery of a series of novel organic reactions has made methylenecyclopropanes (MCPs) some of the most popular building blocks in synthetic organic chemistry during the past two decades. Among reported works, the construction of heterocycles from MCPs has highlighted new synthetic methodologies that afford more opportunities for the quick synthesis of elaborately substituted products, and this should draw a great deal of attention. However, reviews in this area are insufficient, and the latest monograph on heterocycle synthesis from MCPs was published 12 years ago. This review aims to summarize the novel organic reactions of MCPs to produce heterocycles published in recent years, which have provided specific and powerful tools for organic synthesis.