Metal Ion-Catalyzed Hydrolysis of Acrylate Esters and Amides by Way of Their Conjugate Addition Adducts
摘要:
.A formal catalytic cycle for the metal ion-catalyzed hydrolyses of acrylamide and acrylate esters is described. While various transition metal ions show little acceleration of hydrolysis reactions in free water, bringing them into proximity with esters and amides can yield increased hydrolysis rates. Such proximity effects can be brought about by covalent addition of donor atoms near the functional group. However, the simple conjugate adducts of butylmethylamine to methyl acrylate and to acrylamide did not demonstrate metal ion-catalyzed hydrolysis. Conjugate addition of a chelating amine, N-benzyl-N',N'-dimethylethylenediamine, yields adducts demonstrating significant (up to 1.5 x 10(4)-fold) hydrolysis catalysis by Cu(II) at pH 7.5 and room temperature. A model compound to test for improvement of this effect by conformational locking demonstrated no rate increase. A model compound designed to test for enhanced acceleration by two adjacent metal ions similarly showed no rate advantage as compared to the parent conjugate adduct. The conjugate reversion reaction of 3-((2-(dimethylamino)ethyl)benzylamino)propionic acid demonstrated a bell-shaped pH-rate profile with maximum rate at pH 3.
DUERR, BROOK F.;CZARNIK, ANTHONY W., J. CHEM. SOC. CHEM. COMMUN.,(1990) N3, C. 1707-1709
作者:DUERR, BROOK F.、CZARNIK, ANTHONY W.
DOI:——
日期:——
Metal Ion-Catalyzed Hydrolysis of Acrylate Esters and Amides by Way of Their Conjugate Addition Adducts
作者:Mark A. Mortellaro、Thomas J. Bleisch、Brook F. Duerr、Min Sok Kang、Haiyong Huang、Anthony W. Czarnik
DOI:10.1021/jo00127a032
日期:1995.11
.A formal catalytic cycle for the metal ion-catalyzed hydrolyses of acrylamide and acrylate esters is described. While various transition metal ions show little acceleration of hydrolysis reactions in free water, bringing them into proximity with esters and amides can yield increased hydrolysis rates. Such proximity effects can be brought about by covalent addition of donor atoms near the functional group. However, the simple conjugate adducts of butylmethylamine to methyl acrylate and to acrylamide did not demonstrate metal ion-catalyzed hydrolysis. Conjugate addition of a chelating amine, N-benzyl-N',N'-dimethylethylenediamine, yields adducts demonstrating significant (up to 1.5 x 10(4)-fold) hydrolysis catalysis by Cu(II) at pH 7.5 and room temperature. A model compound to test for improvement of this effect by conformational locking demonstrated no rate increase. A model compound designed to test for enhanced acceleration by two adjacent metal ions similarly showed no rate advantage as compared to the parent conjugate adduct. The conjugate reversion reaction of 3-((2-(dimethylamino)ethyl)benzylamino)propionic acid demonstrated a bell-shaped pH-rate profile with maximum rate at pH 3.
Copper(II)-catalysed hydrolysis of an unactivated amide. Application of the groves' rule to the hydrolysis of acrylamide
作者:Brook F. Duerr、Anthony W. Czarnik
DOI:10.1039/c39900001707
日期:——
Conjugate addition of N-benzyl-N′,N′-dimethylethylenediamine to acrylamide affords a chelating amide in which the amide carbonyl can coordinate to the bound metal only via a six-membered chelate; this compound demonstrates copper(II)-catalysed amide hydrolysis, in which each metal acts on at least five equivalents of substrate.