Chemoselective hydrogen peroxide oxidation of primary alcohols to aldehydes by a water-soluble and reusable iron(iii) catalyst in pure water at room temperature

2017 ◽  
Vol 41 (6) ◽  
pp. 2372-2377 ◽  
Author(s):  
Qi Yan ◽  
Ye Chen Fang ◽  
Yun Xue Jia ◽  
Xin Hong Duan

A novel, water-soluble and reusable FeCl3 catalyst showed high catalytic activity and chemoselectivity in the H2O2-oxidation of primary alcohols into aldehydes.

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1078
Author(s):  
Hang Zhang ◽  
Zhipeng Ma ◽  
Yunpeng Min ◽  
Huiru Wang ◽  
Ru Zhang ◽  
...  

Several kinds of composite materials with phosphotungstic acid (PTA) as the catalyst were prepared with activated carbon as support, and their structures were characterized. According to the Box–Behnken central combination principle, the mathematical model of the heterogeneous system is established. Based on the single-factor experiments, the reaction temperature, the reaction time, the amount of hydrogen peroxide and the loading capacity of PTA were selected as the influencing factors to study the catalyzed oxidation of hydrogen peroxide and degradation of high molecular weight chitosan. The results of IR showed that the catalyst had a Keggin structure. The results of the mercury intrusion test showed that the pore structure of the supported PTA catalyst did not change significantly, and with the increase of PTA loading, the porosity and pore volume decreased regularly, which indicated that PTA molecules had been absorbed and filled into the pore of activated carbon. The results of Response Surface Design (RSD) showed that the optimum reaction conditions of supported PTA catalysts for oxidative degradation of high molecular weight chitosan by hydrogen peroxide were as follows: reaction temperature was 70 ℃, reaction time was 3.0 h, the ratio of hydrogen peroxide to chitosan was 2.4 and the catalyst loading was 30%. Under these conditions, the yield and molecular weight of water-soluble chitosan were 62.8% and 1290 Da, respectively. The supported PTA catalyst maintained high catalytic activity after three reuses, which indicated that the supported PTA catalyst had excellent catalytic activity and stable performance compared with the PTA catalyst.


Author(s):  
Mohsen Nikoorazm ◽  
Maryam Khanmoradi ◽  
Masoumeh Sayadian

Introduction:: MCM-41 was synthesized using the sol-gel method. Then two new transition metal complexes of Nickel (II) and Vanadium (IV), were synthesized by immobilization of adenine (6-aminopurine) into MCM-41 mesoporous. The compounds have been characterized by XRD, TGA, SEM, AAS and FT-IR spectral studies. Using these catalysts provided an efficient and enantioselective procedure for oxidation of sulfides to sulfoxides and oxidative coupling of thiols to their corresponding disulfides using hydrogen peroxide at room temperature. Materials and Methods:: To a solution of sulfide or thiol (1 mmol) and H2O2 (5 mmol), a determined amount of the catalyst was added. The reaction mixture was stirred at room temperature for the specific time under solvent free conditions. The progress of the reaction was monitored by TLC using n-hexane: acetone (8:2). Afterwards, the catalyst was removed from the reaction mixture by centrifugation and, then, washed with dichloromethane in order to give the pure products. Results:: All the products were obtained in excellent yields and short reaction times indicating the high activity of the synthesized catalysts. Besides, the catalysts can be recovered and reused for several runs without significant loss in their catalytic activity. Conclusion:: These catalytic systems furnish the products very quickly with excellent yields and VO-6AP-MCM-41 shows high catalytic activity compared to Ni-6AP-MCM-41.


1989 ◽  
Vol 54 (12) ◽  
pp. 3253-3259
Author(s):  
Jaroslav Podlaha ◽  
Miloš Buděšínský ◽  
Jana Podlahová ◽  
Jindřich Hašek

The unusual product of the reaction of 2-chloroacrylonitrile with ethane thiol and following hydrogen peroxide oxidation was found to be (E)-1,2-bis(ethylsulphonyl)cyclobutane-1,2-dicarbonitrile by means of X-ray crystallography. 1H and 13C NMR study of this compound has proven the same conformation of the molecule in solution.


1973 ◽  
Vol 51 (24) ◽  
pp. 4152-4158 ◽  
Author(s):  
Albert Richard Norris ◽  
James William Lennox Wilson

The hydrogen peroxide oxidation of thiocyanate ion in cis- and trans-[Coen2NH3NCS]2+ leads to the formation of the corresponding cis- and trans-cyanoammine- and diamminebis(ethylenediamine)cobalt-(III) complexes. The spectral properties of the previously unreported trans-[Coe2NH3CN]2+ are reported and compared to the spectral properties of the cis-isomer.Observations are made concerning the reaction conditions which favor a high percent conversion of trans-[Coen2NH3NCS]2+ to trans-[Coen2NH3CN]2+.


2016 ◽  
Vol 6 (3) ◽  
pp. 869-874 ◽  
Author(s):  
Shu-Tao Gao ◽  
Weihua Liu ◽  
Cheng Feng ◽  
Ning-Zhao Shang ◽  
Chun Wang

Ag–Pd alloys deposited on an amine-functionalized UiO-66(NH2–UiO-66) have been successfully prepared via a pre-coordination method and used as a AgPd@NH2–UiO-66 catalyst with 100% H2 selectivity and a high catalytic activity.


Sign in / Sign up

Export Citation Format

Share Document