A novel porous metal–organic framework {Cu2(bbda)0.5(Hbbda)1.5(OAc)1.5.8H2O} (UoB‐5) was synthesized under ultrasound irradiation by employing a new Schiff base ligand H2bbda (4,4′(1,4‐phenylene bis (azanylylidene)) bis (methanylylidene))dibenzoic acid) and was fully characterized. The microporous nature of UoB‐5 was confirmed by gas‐sorption measurements. This framework acted as a highly effective heterogeneous catalyst for the alcohol oxidation reaction with tert‐butyl hydroperoxide (t‐BuOOH) as an oxidant. The presence of coordinatively unsaturated metal sites in UoB‐5 could be the reason for high performance in this reaction. Furthermore, using the long linker with the free ‐NC group and uncoordinated ‐N atom on the wall of the pores created UoB‐5 an excellent candidate for the catalytic activities without activation of the framework. It was confirmed with the heterogeneous catalytic experiments on the one‐pot tandem synthesis of imines from benzyl alcohols and anilines. Eventually, the new Cu‐MOF (UoB‐5) could be an alternative catalyst as a more economically favorable and environmentally friendly in the catalysis field.

The design of reusable high-performance heterogeneous catalysts via the immobilization of chemical and biochemical species on magnetic nanoparticles increases the efficiency of catalytic systems by facilitating easy, fast, and clean separation processes. Laccase and 4-amino-2,2,6,6-tetramethylpiperidine-1oxyl were separately immobilized on amine functionalized iron (II, III) oxide nanoparticles with covalent bonding using glutaraldehyde as a coupling reagent. The prepared catalyst was used to synthesize 12 benzoxazole and benzimidazole derivatives. The one-pot, two-step enzymatic aerobic oxidation reaction included the condensation of in situ-produced salicylaldehyde derivatives with aromatic amines, followed by an enzymatic dehydrogenation process. Optimal reaction conditions consisted of a citrate buffer (10 mM, pH 4.5) at 40 8C for an incubation time of 10 h and a heterogeneous catalyst containing immobilized laccase (80 mg, 100 U) and immobilized 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) (40 mg, 2 mol%). The catalyst retained more than 85% of its initial activity after 10 runs. In addition to the potential for reuse without significant losses in performance, eco-friendly attributes of this catalytic system include its high catalytic activity and the ease with which it can be recovered from the reaction mixture using an external magnet.

ZnCr 2 O 7 ·3H 2 O is a readily available and efficient reagent for the one-pot synthesis of a variety of thiosulfonates by chemoselective oxidation of thiols.Thiosulfonates have properties that make them attractive in biology, 1 industry, 2 and organic chemistry. 3 They show antimicrobial and fungicidal activities by blocking the normal metabolism of the microorganism via sulfonation of the enzyme's thiol groups. 1c Thiosulfonates have a wide industrial application both in polymer production and in photographic processes. 2 They have also been extensively utilized in organic synthesis due to their stronger sulfenylating power than disulfides and greater stability and easier handling than sulfinyl chlorides. 3There are several multistep approaches for the synthesis of thiosulfonates including selective reduction of sulfonyl chlorides, 4 reaction of thiosulfonates with diaryliodonium salts, 5 reaction of thiols with sulfonic acid using cyanuric chloride, 6 iodine/bromine oxidative sulfenylation of sulfinates with disulfides, 7 and oxidation of disulfides or thiosulfinates. 8 Thiosulfonates can also be prepared by onepot oxidation of thiols. A literature survey indicates that, in contrast to the numerous methods for the oxidation of thiols to disulfides, few methods are known for the direct synthesis of thiosulfonates from thiols by oxidation. 5,8a-c,9 Moreover, the existing methods suffer from limitations such as the need for special treatment for the activation of the reagent, difficult preparation or unavailability of the reagents, and lack of general applicability to thiol substrates bearing alkyl, aryl, cyclic, and heteroaromatic moieties. Hence, there remains the need for development of new protocols for the synthesis of these important scaffolds.Zinc dichromate trihydrate (ZnCr 2 O 7 ·3H 2 O) which is easily prepared by the reaction of ZnCO 3 with CrO 3 in acidic solution is a stable, cheap, and easy-to-handle compound. 10 It has been used as an efficient reagent for the oxidation of alcohols, sulfides, ethers, acetals, dithioacetals, oximes, silyl and pyranyl ethers. 11 We have recently reported oxidative deamination of amines and a-aminophosphonates, oxidation of a-hydroxyphosphonates, and oxidative deprotection of dithioacetals by ZnCr 2 O 7 ·3H 2 O. 12 To the best of our knowledge, there is no report on the oxidation of thiols by this reagent.In this paper, we wish to report a facile synthesis of thiosulfonates by a one-pot oxidation of thiols in the presence of ZnCr 2 O 7 ·3H 2 O at room temperature.

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The synthesis and characterization of novel Mn-MOF nanostructures (UoB-4) with high performance as catalysts and antibacterial agents.

A novel Ni‐based metal–organic framework (Ni‐MOF) with a Schiff base ligand as an organic linker, Ni3(bdda)2(OAc)2⋅6H2O (H2bdda = 4,4′‐[benzene‐1,4‐diylbis(methylylidenenitrilo)]dibenzoic acid), was synthesized and characterized using powder X‐ray powder diffraction, thermogravimetric analysis, Brunauer–Emmett–Teller measurements, inductively coupled plasma atomic emission spectroscopy, transmission electron microscopy, elemental analysis and Fourier transform infrared spectroscopy. The synthesized Ni‐MOF exhibited a high catalytic activity in benzyl alcohol oxidation using tert‐butyl hydroperoxide under solvent‐free conditions. Also, the efficiency of the catalyst was investigated in the cascade reaction of oxidation–Knoevanagel condensation under mild conditions. The Ni‐MOF catalyst could be recovered and reused four times without significant reduction in its catalytic activity.

MOFs have attracted remarkable attention as solid sorbents in CO2 capture processes for their low-energy post-combustion.

A new method for the efficient synthesis of aldehydes, ketones, and oxophosphonates from various types of amines (primary and secondary) and aminophosphonates via oxidative deamination by nicotinium dichromate (=3‐carboxypyridinium dichromate; NDC) is described.