Journal of Chemical Sciences p. 497 - 507 (2011)
Update date:2022-08-04
Topics:
Dash, Sarat C.
Dash, Anadi C.
The bis phenoxide forms of (1,2) bis(2-hydroxybenzamido) ethane(I) , (1,5) bis(2-hydroxybenzamido) 3-azapentane(II) , (1,3) bis(2-hydroxybenzamido) propane(III) , and (1,8) bis(2-hydroxybenzamido) 3,6- diazaoctane(IV) undergo facile hydrolysis of one of the amide groups (0.02 ≤ [OH?]T (mol dm? 3) ≤ 0.5, 10% MeOH (v/v) + H2O medium) without exhibiting [OH?] dependence. The reactivity trend follows I ~ II >> III ~ IV with low activation enthalpy {25.7±2.8 ≤ δH≠ (kJ mol?1) ≤ 64.8±7.0}. The high negative and comparable values of activation entropy{?234 ±8 ≤ δS≠ (J K?1 mol? 1) ≤ ?127 ± 20} are consistent with closely similar, and ordered transition states which can be assembled by favourably oriented phenoxide groups. The solvent kinetic isotope effect for I, κ H2O/κ D2O+H2O ~ 1 (20 and 50 volume% D2O) , indicates that proton transfer is not involved as a part of the rate controlling process. The observed slowing down of the rate of this reaction for I in the micellar pseudo phase of CTABr also supports the proposed mechanism. Under premicellar conditions, however, rate acceleration is observed, a consequence believed to be associated with the capping effect of the hydrophobic tail of the surfactant cation forming the reactive ion-pair, CTA+, (I-2H) 2? exclusively in the aqueous pseudo phase. Indian Academy of Sciences.
View MoreShangHai Original Economy-Trade Develop Co.,Ltd.,
Contact:86-21-68552131
Address:shanghai
Contact:86-571-61063068
Address:LINAN
YingYing Pharmaceutical Co.,Ltd
Contact:86-18854126208
Address:55#, yingxiongshan road
Ji'nan Orgachem Pharmaceutical Co.,Ltd
Contact:+86-531-82687810
Address:Jinan
Contact:+86-717-6370352
Address:168 Chengdong Avenue, Yichang, Hubei 443003, P. R.China
Doi:10.1021/acs.jmedchem.7b00922
(2017)Doi:10.1002/ejoc.200600488
(2006)Doi:10.1039/P19800002774
(1980)Doi:10.1002/jhet.5570170513
(1980)Doi:10.1002/ejoc.200400156
(2004)Doi:10.1055/s-0034-1378555
(2014)