Facile and efficient hydrolysis of organic halides, epoxides, and esters with water catalyzed by ferric sulfate in a PEG1000-DAIL[BF4]/toluene temperature-dependent biphasic system

2011 ◽  
Vol 35 (2) ◽  
pp. 292-298 ◽  
Author(s):  
Yu Lin Hu ◽  
Hui Jiang ◽  
Jie Zhu ◽  
Ming Lu
Keyword(s):  
Ferric Sulfate ◽  
Biphasic System ◽  
Temperature Dependent ◽  
Organic Halides ◽  
Hydrolysis Of

A PEG1000-DAIL[CdCl3]–toluene temperature-dependent biphasic system that regulates homogeneously catalyzed C–O coupling of organic halides with phenols and alcohols under ligand-free conditions

2011 ◽  
Vol 89 (4) ◽  
pp. 471-480 ◽  
Author(s):  
Yu Lin Hu ◽  
Xiao Yun Ma ◽  
Ming Lu
Keyword(s):  
Catalytic Activity ◽  
Catalytic System ◽  
Biphasic System ◽  
Temperature Dependent ◽  
Convenient Procedure ◽  
Organic Halides ◽  
Ligand Free

An efficient, experimentally simple, and convenient procedure for the C–O coupling of organic halides with phenols and alcohols in a PEG1000-DAIL[CdCl3]–toluene temperature-dependent biphasic system has been developed. The product can be easily isolated by a simple decantation, and the catalytic system can be recycled and reused without loss of catalytic activity.

scholarly journals Solid-Phase “Self-Hydrolysis” of [Zn(NH3)4MoO4@2H2O] Involving Enclathrated Water—An Easy Route to a Layered Basic Ammonium Zinc Molybdate Coordination Polymer

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4022
Author(s):  
Kende Attila Béres ◽  
István E. Sajó ◽  
György Lendvay ◽  
László Trif ◽  
Vladimir M. Petruševski ◽  
...  
Keyword(s):  
Coordination Polymer ◽  
Solid Phase ◽  
Water Molecules ◽  
Temperature Dependent ◽  
Dynamic Interactions ◽  
Ammonia Release ◽  
Successive Substitution ◽  
Red Dye ◽  
Hydrolysis Of ◽  
Zinc Molybdate

An aerial humidity-induced solid-phase hydrolytic transformation of the [Zn(NH3)4]MoO4@2H2O (compound 1@2H2O) with the formation of [(NH4)xH(1−x)Zn(OH)(MoO4)]n (x = 0.92–0.94) coordination polymer (formally NH4Zn(OH)MoO4, compound 2) is described. Based on the isostructural relationship, the powder XRD indicates that the crystal lattice of compound 1@2H2O contains a hydrogen-bonded network of tetraamminezinc (2+) and molybdate (2−) ions, and there are cavities (O4N4(μ-H12) cube) occupied by the two water molecules, which stabilize the crystal structure. Several observations indicate that the water molecules have no fixed positions in the lattice voids; instead, the cavity provides a neighborhood similar to those in clathrates. The @ symbol in the notation is intended to emphasize that the H2O in this compound is enclathrated rather than being water of crystallization. Yet, signs of temperature-dependent dynamic interactions with the wall of the cages can be detected, and 1@2H2O easily releases its water content even on standing and yields compound 2. Surprisingly, hydrolysis products of 1 were observed even in the absence of aerial humidity, which suggests a unique solid-phase quasi-intramolecular hydrolysis. A mechanism involving successive substitution of the ammonia ligands by water molecules and ammonia release is proposed. An ESR study of the Cu-doped compound 2 (2#dotCu) showed that this complex consists of two different Cu2+(Zn2+) environments in the polymeric structure. Thermal decomposition of compounds 1 and 2 results in ZnMoO4 with similar specific surface area and morphology. The ZnMoO4 samples prepared from compounds 1 and 2 and compound 2 in itself are active photocatalysts in the degradation of Congo Red dye. IR, Raman, and UV studies on compounds 1@2H2O and 2 are discussed in detail.

MECHANISM OF ACTIVATION OF HOG PANCREATIC LIPASE BY SODIUM TAUROCHOLATE

1963 ◽  
Vol 41 (1) ◽  
pp. 719-730 ◽  
Author(s):  
Paul J. Fritz ◽  
Paul Melius
Keyword(s):  
Activation Energy ◽  
Enzymatic Hydrolysis ◽  
Pancreatic Lipase ◽  
Sodium Taurocholate ◽  
Enzyme Complex ◽  
Temperature Dependent ◽  
Fast Reaction ◽  
Presence And Absence ◽  
Hydrolysis Of

A new preparation of hog pancreatic lipase is described which is evidently the most stable one of its kind. From the composition of the reaction mixtures after enzymatic hydrolysis with and without sodium taurocholate, it appears that the hydrolysis of triglyceride to diglyceride is facilitated and the hydrolysis of diglyceride to monoglyceride is depressed in the presence of taurocholate. The differences in the curves showing the rates of hydrolysis of triolein, monoolein, tributyrin, and monobutyrin in the presence and absence of taurocholate also indicate that the taurocholate acts to split the diglyceride–enzyme complex and thus increases the action of the enzyme on the triglyceride ester. The hydrolysis of the triglyceride is a fast reaction whereas the di- and mono-glycerides are hydrolyzed at much slower rates. The activation energy for the lipolysis of the triolein and tributyrin has been calculated in the presence and absence of taurocholate. This was possible because in spite of earlier reports that the lipolysis of triolein was not temperature dependent between 10 and 40 degrees, we found these reactions to be temperature dependent. The lesser activating effect at the highest taurocholate concentrations indicates this is not a simple emulsifying effect.

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