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Abstract Aimed at energy conservation and water saving for the lab, we have designed and constructed one kind of lab-scale small recirculating device of cooling water utilizing a water recirculator coupled to a solar energy system via a self-made multifunctional voltage regulator, which is equipped with an active heat radiator and powered by a solar energy system. It can provide cooling water for 1–3 sets of ordinary refluxing setups in series without additional consumption of water and electricity. The temperature difference between the water in the bucket and the environment is less than 4 °C for eight common solvents in single refluxing set-up or three combined refluxing setups with different solvents in series. In the performance assessment experiments for the refluxing of eight common solvents with different boiling point, the largest solvent loss is less than 6% if the condenser is open to the air in the refluxing time of 8 h, but none obvious solvent loss are found if the condensers were equipped with an oil bubbler. Control experiments indicates that the preparation of bromoethane/ethyl acetate/propyl hexanoate using our water recirculator can achieve almost unanimous yields in relative to those reactions using tap water as cooling water.

In this study, we present a comprehensive overview of supramolecular self-assemblies comprising cyclodextrins (CDs) and polyoxometalates (POMs). We summarize the recent advancements in supramolecular POM–CD systems, including their structures, functions, and applications. Subsequently, we focus on the self-assembly behavior of CDs and POMs, encompassing the formation of inclusion complexes, host–guest interactions, and the development of hybrid materials. In addition, we discuss the remarks on future outlooks and hope that this review will serve as a valuable reference for researchers engaged in the fields of supramolecular/POM chemistry, materials science, and nanotechnology.

Using chain-like polyethers consisting of two terminal –NH2 groups and (TBA)4[α-Mo8O26] as starting materials, two polyoxometalatocrown ethers were prepared by a cyclization reaction through the formation of Mo≡N triple bonds: (TBA)2[Mo6O17N(o-C6H4OCH2(CH2OCH2)nCH2OC6H4-o)N] (compounds 1, n = 1; 2, n = 2). As confirmed by single-crystal X-ray diffraction and infrared (IR) studies, the polyoxometalatocrown ether 2 can capture primary ammonium cations in solid state.

Heteroatoms are very important in polyoxometalates (POMs) because they can lead to appealing architectures and unexpected properties in the final POMs. In this work, we elaborately designed and isolated three Silverton-type POMs ([UIVMo12O42] 8−) with UIV as the heteroatom and linked by FeII (FeUMo), CoII (CoUMo) and NiII (NiUMo). These Silverton-type U-containing polyoxomolybdates were demonstrated to be the first molecular catalysts for the synthesis of quinazolinone drug precursor skeletons. Under the optimized reaction conditions, 27 quinazolinones could be obtained in high yield with water as the sole by-product under mild conditions. Furthermore, NiUMo can be recycled seven times and still keep high stability and catalytic activity. [ABSTRACT FROM AUTHOR]

Thiosulfonates and disulfides are important scaffolds in bioactive molecules and drugs, yet methods for the synthesis of these compounds that start from simple and commercially available feedstocks with sustainable routes are scarce. In this report, we present a green protocol for the synthesis of these valuable S-S motifs through selective oxidation of thiols using H2O2 or air as oxidant and anionic polyoxomolybdate (Mo8O26 4-) as catalyst. Notable features of this method are scalability, operational simplicity, broad functional-group compatibility, and good chemoselectivity. Mechanistic studies, such as radical trapping experiments, kinetic experiments, cyclic voltammetry, ultraviolet-visible spectroscopy, infrared spectroscopy and Raman spectral monitoring of the reaction mixture support formation of a molybdenum(V)-hydroxo-species and a molybdenum (VI)-peroxo-species to drive the two different catalytic cycles, respectively. [ABSTRACT FROM AUTHOR]