METAL ION-CATALYZED HYDROLYSIS OF ACRYLATE ESTERS AND AMIDES BY WAY OF THEIR CONJUGATE ADDITION ADDUCTS

.A formal catalytic cycle for the metal ion-catalyzed hydrolyses of ac rylamide and acrylate esters is described. While various transition me tal ions show little acceleration of hydrolysis reactions in free wate r, bringing them into proximity with esters and amides can yield incre ased hydrolysis rates. Such proximity effects can be brought about by covalent addition of donor atoms near the functional group. However, t he simple conjugate adducts of butylmethylamine to methyl acrylate and to acrylamide did not demonstrate metal ion-catalyzed hydrolysis. Con jugate addition of a chelating amine, N-benzyl-N',N'-dimethylethylened iamine, yields adducts demonstrating significant (up to 1.5 x 10(4)-fo ld) hydrolysis catalysis by Cu(II) at pH 7.5 and room temperature. A m odel compound to test for improvement of this effect by conformational locking demonstrated no rate increase. A model compound designed to t est for enhanced acceleration by two adjacent metal ions similarly sho wed 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 maximu m rate at pH 3.