HYDROLYSIS OF UNACTIVATED ESTERS AND ACETONITRILE HYDRATION BY A HYDROXO-DICOPPER(II) COMPLEX

Binuclear metal-hydroxide centers are implicated in many protein hydro lases. Here, we show that the binucleating ligand '-tetrakis(2-pyridyl methyl)-1,3-diamino-2-propanol (L-OH) reacts with 2 equiv of Cu-I and O-2, giving the tetranuclear complex [Cu-4(L-O-)(2)(mu-OH-)(2)](4+) (1 ) (X-ray), established to give binuclear species 2 upon dissolution in CH3CN. Labeling experiments show that the hydroxide moiety in 2 acts as a nucleophile for the efficient hydrolysis of unactivated acetate e sters, yielding the mu-acetato-bridged complexes 3. Species 2 also slo wly hydrates acetonitrile, yielding the mu-amidate-dicopper(II) comple x 4.