W. B. S. Newling

Bio: W. B. S. Newling is an academic researcher. The author has contributed to research in topics: Hydrolysis constant & Alkaline hydrolysis. The author has an hindex of 1, co-authored 1 publications receiving 26 citations.

Chapter 2 Hydrolysis and Formation of Esters of Organic Acids

Abstract: Publisher Summary The hydrolysis and formation of esters have been extensively studied than any other chemical reaction. This chapter brings together in one place a representative selection of the data to set them in the perspective of an overall view of the subject and to offer the interpretation of each type of reaction that seems most acceptable in the light of current knowledge. Simple carboxylic acids and their esters are weak bases. They are completely protonated only in very strong acidic media. The chapter reviews the recent investigations of ester hydrolysis in concentrated solutions of strong mineral acids. It is now possible to study the hydrolysis reactions of esters under conditions where the substrate is completely protonated. The properties of the protonated ester, however, are more conveniently examined using more strongly acidic media, in the absence of water, where bimolecular reactions are reduced to insignificance. At sufficiently low temperatures under these conditions, the rates of exchange of the added protons are slow and the detailed structures of protonated carboxylic acids and esters can be investigated, particularly by proton nuclear magnetic resonance (NMR) techniques.

A DFT investigation of methanolysis and hydrolysis of triacetin

Abstract: The thermodynamic and kinetic aspects of the methanolysis and hydrolysis reactions of glycerol triacetate or triacetin, a model triacylglycerol compound, were investigated by using Density Functional Theory (DFT) at the B3LYP/6-31++G(d,p) level of calculation. Twelve elementary steps of triacetin methanolysis were studied under acid-catalyzed and base-catalyzed conditions. The mechanism of acid-catalyzed methanolysis reaction which has not been reported yet for any esters was proposed. The effects of substitution, methanolysis/hydrolysis position, solvent and face of nucleophilic attack on the free energy of reaction and activation energy were examined. The prediction confirmed the facile position at the middle position of glycerol observed by NMR techniques. The calculated activation energy and the trends of those factors agree with existing experimental observations in biodiesel production.