A Quantitative Description of the Effect of Cetyltrimethylammonium Bromide on the 2-Iodosylbenzoate Catalyzed Hydrolysis of Active Esters and Related Compounds

1989 ◽  
Vol 42 (12) ◽  
pp. 2119 ◽  
Author(s):  
DR Leslie
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Quantitative Description ◽  
Active Esters ◽  
Hydrolysis Of ◽  
Related Compounds

The Effect of Cetyltrimethylammonium Bromide on the 2-Iodosyl-5-octyloxy-benzoate-Catalyzed Hydrolysis of Active Esters and Related Compounds

1990 ◽  
Vol 43 (5) ◽  
pp. 937 ◽  
Author(s):  
DR Leslie ◽  
S Pantelidis
Keyword(s):  
Phase Separation ◽  
Cetyltrimethylammonium Bromide ◽  
Active Esters ◽  
Diphenyl Phosphate ◽  
Hydrolysis Of ◽  
Related Compounds ◽  
Separation Model

Enhancements provided by micellized cetyltrimethylammonium bromide ( ctab ), to the rates of reaction between 2-iodosyl-5-octyloxybenzoic acid and 4-nitrophenyl diphenyl phosphate (3), 4-nitrophenyl acetate (4), 1-methylethyl methylphosphonofluoridate (5), 1,2,2-trimethylpropyl methylphosphonofluoridate (6) and ethyl N,N- dimethylphosphoramidocyanidate (7) are determined over a range of ctab concentrations. The maximum enhancements observed for substrates (5)-(7) are greater than predicted by the phase-separation model.1 The suitability of themodel to describe these reactions is considered.

Synthesis and Tautomerism of Curcumin Derivatives and Related Compounds

2015 ◽  
Vol 68 (2) ◽  
pp. 224 ◽  
Author(s):  
Hiroyasu Taguchi ◽  
Daijiro Yanagisawa ◽  
Shigehiro Morikawa ◽  
Koichi Hirao ◽  
Nobuaki Shirai ◽  
...  
Keyword(s):  
Parent Compound ◽  
Amyloid Plaques ◽  
Enol Form ◽  
19F Nmr ◽  
Enolic Form ◽  
Curcumin Derivatives ◽  
Alkyl Groups ◽  
Alzheimer Brain ◽  
Hydrolysis Of ◽  
Related Compounds

1,7-Bis(4′-hydroxy-3′-trifluoromethoxyphenyl)-1,6-heptadiene-3,5-dione (2a), related to curcumin, and thirteen 4-substituted derivatives were prepared and their keto/enol ratio in DMSO[D6] was determined by 19F NMR because the enolic form of these related curcumins had been shown to bind to amyloid plaques in the Alzheimer brain. The parent compound and the 4-ethoxycarbonyl derivative were almost 100 % in the enolic form that contains a conjugated hepta-1,4,6-trien-3-on-5-ol backbone. Enolisation decreased to varying amounts in the derivatives that had 4-substituted alkyl groups. Attempts to prepare the 4-hydroxypropyl derivative by hydrolysis of O-methoxymethyl 2m or O-tetrahydropyranyloxy 2n protected derivatives led to cyclised products. A related pyrimidine compound 6b that mimicked a fixed enol form was also prepared.

Micellar catalysis of organic reactions. VIII. Kinetic studies of the hydrolysis of 2-acetyloxybenzoic acid (aspirin) in the presence of micelles

1982 ◽  
Vol 35 (7) ◽  
pp. 1357 ◽  
Author(s):  
TJ Broxton
Keyword(s):  
Aqueous Solution ◽  
Cetyltrimethylammonium Bromide ◽  
Cetylpyridinium Chloride ◽  
Kinetic Studies ◽  
Base Catalysis ◽  
Plateau Region ◽  
General Base ◽  
Mechanism Of Hydrolysis ◽  
Ph Range ◽  
Hydrolysis Of

The hydrolysis of 2-acetyloxybenzoic acid in the pH range 6-12 has been studied in the presence of micelles of cetyltrimethylammonium bromide (ctab) and cetylpyridinium chloride (cpc). In the plateau region (pH 6-8) the hydrolysis is inhibited by the presence of micelles, while in the region where the normal BAC2 hydrolysis (pH > 9) occurs the reaction is catalysed by micelles of ctab and cpc. The mechanism of hydrolysis in the plateau region is shown to involve general base catalysis by the adjacent ionized carboxy group both in the presence and absence of micelles. This reaction is inhibited in the presence of micelles because the substrate molecules are solubilized into the micelle and water is less available in this environment than in normal aqueous solution.

scholarly journals Kinetics of the alkaline hydrolysis of crystal violet in micelles, reverse micelles and microemulsions of cetyltrimethylammonium bromide

1970 ◽  
Vol 24 (2) ◽  
pp. 173-184 ◽  
Author(s):  
Ferdousi Begum ◽  
Md Yousuf A Molla ◽  
M Muhibur Rahman ◽  
Md Abu Bin Hasan Susan
Keyword(s):  
Crystal Violet ◽  
Alkaline Hydrolysis ◽  
Reverse Micelles ◽  
Cetyltrimethylammonium Bromide ◽  
Specific Conductivity ◽  
Water System ◽  
Chemical Society ◽  
Order Rate Constant ◽  
Kinetics Of ◽  
Hydrolysis Of

Kinetics of the alkaline hydrolysis of crystal violet (CV) in micelles, reverse micelles and microemulsions of a cationic surfactant, cetyltrimethylammonium bromide (CTAB) was studied at 25 ± 0.1 oC using spectrophotometric method. The rate of alkaline hydrolysis of CV was catalyzed by micellar solutions of CTAB. The pseudo first order rate constant (k') has been found to decrease upon incorporation of 1-butanol to cationic CTAB micelles, which displaces the substrate from the micellar into the aqueous phase. In CTAB/cyclohexane/1-butanol/water system, as the content of 1-butanol increases, specific conductivity and density of the microemulsions and reverse micelles decrease. The change in physical properties also causes change in reaction environment. A change from a micelle-rich (o/w) to a reverse micelle-rich (w/o) condition is apparent for microemulsions and consequently the k' vs. % wt. of 1-butanol profiles show an initial decrease in the k' followed by a gradual increase and finally, to a sharp increase with increasing 1-butanol content. Microemulsions and reverse micelles thus offer the potential to control rate of a reaction by formation of micelles in water phase and reverse micelles in oil phase. DOI: http://dx.doi.org/10.3329/jbcs.v24i2.9706 Journal of Bangladesh Chemical Society, Vol. 24(2), 173-184, 2011

Micelle Catalyzed Hydrolysis of Carboxylic Acid Esters in Water–β‐Cyclodextrin–Cetyltrimethylammonium Bromide Systems

2003 ◽  
Vol 24 (1) ◽  
pp. 97-101 ◽  
Author(s):  
Jiaqing Xie ◽  
Yi Zhang ◽  
Juan Du ◽  
Xian‐cheng Zeng ◽  
Ying‐jin Liu ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Cetyltrimethylammonium Bromide ◽  
Hydrolysis Of ◽  
Acid Esters
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