Dinuclear Zn2+ metal complexes based on 1,10-phenanthroline derivates as catalysts for the hydrolysis of 2-hydroxypropyl-p-nitrophenyl phosphate (HPNP) and p-nitrophenyl phosphate (NPP)

Abstract

One multidentate ligand, 1,13-di-(1,10-phenanthroline-2-methylene)-1,4,7,10,13-pentaazatridecane(L), has been synthesized and characterized. The kinetics of hydrolysis of 2-hydroxypropyl-p-nitrophenyl phosphate (HPNP) and p-nitrophenyl phosphate (NPP) catalyzed by complexes of L with Zn 2+ have been studied. Both Zn 2 L and Zn 2 LH )1 had the ability to catalysis a hydrolysis of HPNP and NPP, and the kinetics of hydrolysis of HPNP and NPP were examined in aqueous solution at 25.0 ± 0.1°C, I = 0.1 mol dm )3 KNO 3 at the pH range of 7.0-8.5, respectively. Kinetic studies showed that Zn 2 LH )1 was a more active species than Zn 2 L in the hydrolysis of HPNP and NPP. A new mechanism was proposed for the hydrolysis of HPNP and NPP catalyzed by Zn 2 L and Zn 2 LH )1 .

Phosphate monoester hydrolysis at tricopper site: The advantage and disadvantage of closely assembled trimetallic active sites

“…In addition, both tricopper complexes are much more effective in catalyzing NPP hydrolysis than the mononuclear [Cu(tacn)] 2+ analog with an equal concentration of Cu(II). This result is consistent with previous findings that vicinal metal ions in a single molecule can function cooperatively for phosphate hydrolysis [70][71][72][73][74].…”