The Effects of Organic Solvents on Catalytic Behavior of Immobilized Hemoglobin Nanocomposites: Functional Groups and Molecular Constitution

2011 ◽  
Vol 233-235 ◽  
pp. 1556-1559
Author(s):  
Shu Ge Peng ◽  
Yong Ke Guo ◽  
Xiao Fei Liu ◽  
Jun Zhang

The use of organic solvents as reaction media for enzymatic reactions provides numerous industrially attractive advantages compared to traditional aqueous reaction systems. Hemoglobin (Hb) intercalated magadiite nano-composites was successfully prepared by exfoliation-reassembly method at room temperature and pH=7, and was used to catalyze the oxidation of o-phenylenediamine in organic solvents. Catalytic activity of immobilized Hb in organic solvents with different hydrophobicity and different functional groups were investigated detailedly. The results showed that functional groups and molecular constitution of the organic solvents were both important factors to determine catalytic activity of immobilized Hb in organic media except hydrophobicity of organic solvents.

2014 ◽  
Vol 636 ◽  
pp. 93-96
Author(s):  
Ming Zhang ◽  
Wen Shuai Zhu ◽  
Meng Li ◽  
Yan An Li ◽  
Suhang Xun ◽  
...  

Tungsten-containing functional mesoporousW-SiO2 have been successfully synthesized by an one-pot and facile room-temperature procedure. These materials presented a high dispersion of tungsten species and excellent catalytic activity on the removal of sulfur compounds without any organic solvents as extractants. The catalytic performance on sulfur compounds was investigated in detail. After recycling for 8 times, the removal of the oxidation desulfurization system could still reach 92.0%.


2017 ◽  
Vol 23 (6) ◽  
Author(s):  
Mohammad Nikpassand ◽  
Leila Zare Fekri ◽  
Hasti Taherkhorsand

Abstract2-Oxoimidazolidine-1,3-disulfonic acid (OImDSA) is a recoverable catalyst for the synthesis of 1,3-thiazolidine-4-ones at room temperature in a one-pot procedure without using any organic solvents. Moreover, the catalyst can be easily recovered and recycled for five runs without significant loss of catalytic activity. The structures of the synthesized 1,3-thiazolidine-4-one compounds were confirmed by


2019 ◽  
Author(s):  
Meifeng Wang ◽  
Liyin Zhang ◽  
Yiqun Li ◽  
Liuqun Gu

<p></p>Anomerization of glycosides were rarely performed under basic condition due to lack of efficiency. Here an imidazole promoted anomerization of β-D-glucose pentaacetate was developed; and reaction could proceed in both organic solvents and solid state at room temperature. Although mechanism is not yet clear, this unprecedent mild anomerization in solid state may open a new promising way for stereoseletive anomerization of broad glucosides and materials design in the future..


2019 ◽  
Vol 23 (16) ◽  
pp. 1778-1788 ◽  
Author(s):  
Gurpreet Kaur ◽  
Arvind Singh ◽  
Kiran Bala ◽  
Mamta Devi ◽  
Anjana Kumari ◽  
...  

A simple, straightforward and efficient method has been developed for the synthesis of (E)-3-(arylimino)indolin-2-one derivatives and (E)-2-((4-methoxyphenyl)imino)- acenaphthylen-1(2H)-one. The synthesis of these biologically-significant scaffolds was achieved from the reactions of various substituted anilines and isatins or acenaphthaquinone, respectively, using commercially available, environmentally benign and naturally occurring organic acids such as mandelic acid or itaconic acid as catalyst in aqueous medium at room temperature. Mild reaction conditions, energy efficiency, good to excellent yields, environmentally benign conditions, easy isolation of products, no need of column chromatographic separation and the reusability of reaction media are some of the significant features of the present protocol.


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.


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