Examination of P-OR bridging bond orders in phosphate monoesters using (18)O isotope shifts in 31P NMR.


Evidence indicates that phosphate monoesters undergo hydrolysis by a loose transition state with extensive bond fission to the leaving group. It has been proposed that part of the high dependence of the rate on the leaving group pKa (betalg = -1.23) arises from weaker ester bonds in the reactants as the pKa of the leaving group decreases, on the basis of X… (More)