Dinuclear lanthanum complex catalyzes the hydrolysis of a phosphate diester with unprecedented speed

Abstract

The dihydroxo dilanthanum macrocyclic complex hydrolyzes bis(p-nitrophenyl) hydrogen phosphate (BNP) with a remarkably high rate constant and a unique third-order dependence on the concentration of the dinuclear complex.

References

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6. A k_cat value of 0.0004 s^–1 was measured at pH 7.0 by using [LLa₂]_TOT= 5.0 mM and [BNP]_INIT= 0.5 mM. The rate enhancement over spontaneous hydrolysis is 1.2 × 10⁷. A k_cat value at pH 10.0, with the concentrations just described, is too fast to measure by our method. By extrapolation, it calculates to k_cat= 0.32 s^–1 which is one turnover every 3–4 s. This is a rate enhancement of 1.2 × 10⁸.