Nature of the rate acceleration due to added dioxane on the hydrolysis of an .alpha.,.beta.-unsaturated Schiff base

1978 ◽  
Vol 43 (25) ◽  
pp. 4709-4712 ◽  
Author(s):  
Margaret Brault ◽  
Robert H. Kayser ◽  
Ralph M. Pollack
Keyword(s):  
Schiff Base ◽  
Rate Acceleration ◽  
Alpha Beta ◽  
Hydrolysis Of

Schiff base equilibria. II. Beryllium complexes of N-n-butylsalicylideneimine and the hydrolysis of the Be2+ ion

1965 ◽  
Vol 18 (5) ◽  
pp. 651 ◽  
Author(s):  
RW Green ◽  
PW Alexander
Keyword(s):  
Aqueous Solution ◽  
Schiff Base ◽  
Complex Formation ◽  
Distribution Coefficient ◽  
Dilute Aqueous Solution ◽  
The Stability ◽  
Ph Range ◽  
Hydrolysis Of ◽  
Beryllium Complexes ◽  
Equilibria In Aqueous Solution

The Schiff base, N-n-butylsalicylideneimine, extracts more than 99.8% beryllium into toluene from dilute aqueous solution. The distribution of beryllium has been studied in the pH range 5-13 and is discussed in terms of the several complex equilibria in aqueous solution. The stability constants of the complexes formed between beryllium and the Schiff base are log β1 11.1 and log β2 20.4, and the distribution coefficient of the bis complex is 550. Over most of the pH range, hydrolysis of the Be2+ ion competes with complex formation and provides a means of measuring the hydrolysis constants. They are for the reactions: Be(H2O)42+ ↔ 2H+ + Be(H2O)2(OH)2, log*β2 - 13.65; Be(H2O)42+ ↔ 3H+ + Be(H2O)(OH)3-, log*β3 -24.11.

A Selective Colorimetric and Fluorescent Chemodosimeter for Fe(III) Ion Based on Hydrolysis of Schiff Base

2015 ◽  
Vol 62 (4) ◽  
pp. 316-320 ◽  
Author(s):  
Haw-Tyng Tsai ◽  
Yeshwant Ramchandra Bhorge ◽  
Albert J. Pape ◽  
Sudhakar Narasimha Janaki ◽  
Yao-Pin Yen
Keyword(s):  
Schiff Base ◽  
Fluorescent Chemodosimeter ◽  
Hydrolysis Of

SUBSTITUTION AT OCTAHEDRAL CENTERS: II. EFFECT OF SALTS UPON THE RATE OF HYDROLYSIS OF THE HALOPENTAMMINECHROMIUM(III) IONS

1961 ◽  
Vol 39 (11) ◽  
pp. 2371-2379 ◽  
Author(s):  
T. P. Jones ◽  
W. E. Harris ◽  
W. J. Wallace
Keyword(s):  
Charge Transfer ◽  
Transfer Effect ◽  
Ion Pair ◽  
Pair Formation ◽  
Sodium Salts ◽  
Rate Acceleration ◽  
Rate Of Hydrolysis ◽  
A Charge ◽  
Hydrolysis Of ◽  
Octahedral Configuration

A study of the hydrolysis of the halopentamminechromium(III) ions in the presence of the sodium salts of weak acids reveals a rate acceleration due to specific ion-pair formation. The acceleration is due partly to a charge-transfer effect and partly to the fact that the ion helps to maintain the octahedral configuration of the complex in the transition state. It is concluded that the reaction occurs by dissociation, but without collapse of the structure to a five-co-ordinated intermediate.

scholarly journals Acid Hydrolysis of Some alpha,beta-Unsaturated Aliphatic Esters.

1956 ◽  
Vol 10 ◽  
pp. 1355-1356 ◽  
Author(s):  
Eero A. Halonen ◽  
Agneta Rosenberg ◽  
H. I. Waterman ◽  
N. A. Eliasson ◽  
B. Thorell
Keyword(s):  
Acid Hydrolysis ◽  
Aliphatic Esters ◽  
Alpha Beta ◽  
Hydrolysis Of

A “turn-on” fluorescent and colorimetric chemodosimeter for selective detection of Au3+ ions in solution and in live cells via Au3+-induced hydrolysis of a rhodamine-derived Schiff base

2020 ◽  
Vol 44 (19) ◽  
pp. 7954-7961
Author(s):  
Sanchita Mondal ◽  
Saikat Kumar Manna ◽  
Sudipta Pathak ◽  
Aritri Ghosh ◽  
Pallab Datta ◽  
...  
Keyword(s):  
Schiff Base ◽  
Rhodamine B ◽  
Aqueous Media ◽  
Sensitive Detection ◽  
Live Cells ◽  
Selective Detection ◽  
Turn On ◽  
Hydrolysis Of

A chromogenic and “off–on” fluorogenic chemodosimeter (L) based on a naphthalene–rhodamine B derivative was designed, synthesized and characterized for the selective and sensitive detection of Au3+ ions in mixed acetonitrile aqueous media.

scholarly journals Thermal Healing, Reshaping and Ecofriendly Recycling of Epoxy Resin Crosslinked with Schiff Base of Vanillin and Hexane-1,6-Diamine

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 293 ◽  
Author(s):  
Van-Dung Mai ◽  
Se-Ra Shin ◽  
Dai-Soo Lee ◽  
Ilho Kang
Keyword(s):  
Schiff Base ◽  
Epoxy Resin ◽  
Elevated Temperatures ◽  
Relaxation Times ◽  
Diglycidyl Ether ◽  
Original Material ◽  
Crosslinked Polymer ◽  
Schiff Base Formation ◽  
Hydrolysis Of ◽  
Base Formation

A bio-derived dihydroxylimine hardener, Van2HMDA, for the curing of epoxy resin was prepared from vanillin (Van) and hexamethylene-1,6-diamine (HMDA) by Schiff base formation. The epoxy resin of diglycidyl ether of bisphenol A was cured with Van2HMDA in the presence of the catalyst, 2-ethyl-4-methylimidazole (EMI). The crosslinked epoxy resin showed thermal-healing properties at elevated temperatures. Moreover, the crosslinked epoxy resin can be reshaped by heating via imine metathesis of the hardener units. The imine metathesis of Van2HMDA was confirmed experimentally. Stress-relaxation properties of the epoxy resin crosslinked with Van2HMDA were investigated, and the activation energy obtained from Arrhenius plots of the relaxation times was 44 kJ/mol. The imine bonds in the epoxy polymer matrix did not undergo hydrolysis after immersing in water at room temperature for one week. However, in the presence of acid, the crosslinked polymer was easily decomposed due to the hydrolysis of imine bonds. The hydrolysis of imine bonds was used for the ecofriendly recycling of crosslinked polymer. It is inferred that thermal-healing, reshaping, and reprocessing properties can be implemented in the various crosslinked epoxy resins with the bio-derived dihydroxylimine hardener, albeit the recycled epoxy resin is of inevitably lower quality than the original material.

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