Abstracto
- The "water terms" for the hydrolysis of ethyl trifluoroacetate (which is subject to protolytic general-base catalysis) and for the hydrolysis of ethyl o-nitrophenyl oxalate (which shows nucleophilic general-base catalysis) produce solvent isotope effects and dependences of rate constant on atom fraction of deuterium ("proton inventories") which are consistent with the presence of an "immature hydronium ion" in the transition state, bridging to the remainder of the structure through an unusually strong type of hydrogen bond. A number of other reactions are probably subject to this kind of catalysis.