Catalytic hydrolysis of phosphate esters by metallocomplexes of 1,10-phenanthroline derivatives in micellar solution

Article abstract of DOI:10.1002/recl.19931120608

Divalent metal-ion complexes of 2,9-bis<(methyldodecylamino)methyl>-1,10-phenanthroline (C12Phen-M^II) in neutral Brij 35 micelles catalyse the hydrolysis of various phosphate triesters, diesters and monoesters.The catalytic activity of C12Phen-M^II has been compared with that of the metal-ion complexes of its water-soluble counterpart 2,9-bis<(dimethylamino)methyl>-1,10-phenanthroline (C1Phen-M^II).Saturation kinetics provide evidence for preliminary formation of ligand-MII-phosphate ester complexes, which decay to products.The hydroysis of diphenyl 4-nitrophenyl phosphate (1b) coordinated to C12Phen-Zn^II proceeds 8700 times faster than the hydrolysis of 1b in the absence of metallocatalyst.Kinetic studies indicate that phosphate triesters containing a metal-ion-binding site in close proximity to the phosphoryl bond, i.e., diphenyl 5-nitro-2-pyridyl phosphate (2b) and diphenyl 5-nitro-8-quinolyl phosphate (3), are hydrolysed by the same mechanism as 1b.