A mechanistic study of the base-catalyzed methanolysis and hydrolysis of the hydrogen phthalate ester of 4-bromo-4′-nitrobenzhydrol

1969 ◽  
Vol 47 (9) ◽  
pp. 1487-1493
Author(s):  
K. G. Rutherford ◽  
O. A. Mamer ◽  
B. K. Tang
Keyword(s):  
Carboxylate Anion ◽  
Phthalate Ester ◽  
Mechanistic Study ◽  
Hydrogen Phthalate ◽  
Isotope Studies ◽  
O Isotope ◽  
Hydrolysis Of

The hydrogen phthalate ester of 4-bromo-4′-nitrobenzhydrol has been subjected to base-catalyzed methanolysis and hydrolysis. In both cases the BAC2 mechanism has been observed. There is no evidence of ortho-carboxylate anion participation (BAC1 mechanism). The results have been substantiated by kinetics, stereochemistry, and 18O isotope studies.

scholarly journals Kinetics and Mechanistic Study of Hydrolysis of Adenosine Monophosphate Disodium Salt (AMPNa2) in Acidic and Alkaline Media

2019 ◽  
Vol 17 (1) ◽  
pp. 544-556
Author(s):  
Yoke-Leng Sim ◽  
Beljit Kaur
Keyword(s):  
Rate Constant ◽  
Adenosine Monophosphate ◽  
Disodium Salt ◽  
Second Order ◽  
Information Storage ◽  
Alkaline Media ◽  
Basic Medium ◽  
Mechanistic Study ◽  
Phosphate Ester ◽  
Hydrolysis Of

AbstractPhosphate ester hydrolysis is essential in signal transduction, energy storage and production, information storage and DNA repair. In this investigation, hydrolysis of adenosine monophosphate disodium salt (AMPNa2) was carried out in acidic, neutral and alkaline conditions of pH ranging between 0.30-12.71 at 60°C. The reaction was monitored spectrophotometrically. The rate ranged between (1.20 ± 0.10) × 10-7 s-1 to (4.44 ± 0.05) × 10-6 s-1 at [NaOH] from 0.0008 M to 1.00M recorded a second-order base-catalyzed rate constant, kOH as 4.32 × 10-6 M-1 s-1. In acidic conditions, the rate ranged between (1.32 ± 0.06) × 10-7 s-1 to (1.67 ± 0.10) × 10-6 s-1 at [HCl] from 0.01 M to 1.00 M. Second-order acid-catalyzed rate constant, kH obtained was 1.62 × 10-6 M-1 s-1. Rate of reaction for neutral region, k0 was obtained from graphical method to be 10-7 s-1. Mechanisms were proposed to involve P-O bond cleavage in basic medium while competition between P-O bond and N-glycosidic cleavage was observed in acidic medium. In conclusion, this study has provided comprehensive information on the kinetic parameters and mechanism of cleavage of AMPNa2 which mimicked natural AMP cleavage and the action of enzymes that facilitate its cleavage.

A Mechanistic Study of the Hydrolysis of Poly[N,N-(dimethylamino)ethyl acrylates] as Charge-Shifting Polycations

2020 ◽  
Vol 53 (9) ◽  
pp. 3514-3523 ◽  
Author(s):  
Samantha Ros ◽  
Jiexi Wang ◽  
Nicholas A. D. Burke ◽  
Harald D. H. Stöver
Keyword(s):  
Mechanistic Study ◽  
Hydrolysis Of

A New Insight into the Mechanistic Study on Synthesis of Silica Nanospheres

2007 ◽  
Vol 124-126 ◽  
pp. 1249-1252
Author(s):  
Dong Shin Yun ◽  
Hyun Jung Kim ◽  
Hyun Chang Shin ◽  
Venkatathri Narayanan ◽  
Jung Whan Yoo ◽  
...  
Keyword(s):  
Physicochemical Characteristics ◽  
Mechanistic Study ◽  
Partial Hydrolysis ◽  
Particle Sizes ◽  
Species Concentration ◽  
Surface Areas ◽  
Ft Ir ◽  
Alkoxy Groups ◽  
Hydrolysis Of ◽  
Insight Into

The physicochemical characteristics (SEM, N2 adsorption, FT-IR, MASNMR) of samples from kinetics (10 min, 20 min, 30 min, 1 h and 3h) of hydrolysis of tetraethyl orthosilicate (TEOS) gives new insight into the synthesis of nanosphere. The particle sizes are increased with time, however, the surface areas decreased. FT-IR investigation reveals the presence of high intensed silanol groups of 960 cm-1 at 10 min, which reduced on progress of the reaction time. This suggests the partial hydrolysis and condensation of alkoxy groups in TEOS. 29Si MASNMR analysis shows the presence three different silica species(Q4, Q3 and Q2) in 10 and 20 min samples. The intensity of Q2 species decreases with time and other species concentration were increased.

scholarly journals Modeling the Alkaline Hydrolysis of Diaryl Sulfate Diesters: A Mechanistic Study

2020 ◽  
Vol 85 (10) ◽  
pp. 6489-6497
Author(s):  
Klaudia Szeler ◽  
Nicholas H. Williams ◽  
Alvan C. Hengge ◽  
Shina C. L. Kamerlin
Keyword(s):  
Alkaline Hydrolysis ◽  
Mechanistic Study ◽  
Hydrolysis Of
Sign in / Sign up

Export Citation Format

Share Document