Kinetics and mechanisms of the formation and reactions of alkyl nitrites

Abstract

The work in this thesis is concerned with the kinetics and mechanisms of reactions involving 0-nitrosation.The introductory chapter provides a brief survey of the literature concerning nitrosation at nitrogen, oxygen and sulphur. The first experimental chapter deals with the kinetics of 0-nitrosation in aqueous acidic solution leading to the formation of alkyl nitrites. Equilibrium constants for the formation of the alkyl nitrites were measured together with rate constants for the forward and reverse reactions. Rate and equilibrium constants were also determined for some carbohydrates. The involvement of alkyl nitrites as possible nitrosating agents in aqueous alcoholic solutions containing acids and sodium nitrite was also investigated. The results obtained demonstrated that these nitrosation reactions occur via nitrous acid and the alkyl nitrites are almost totally ineffective as nitrosating agents. The effect of other additives (which could, in theory, form 0-nitroso or S-nitroso species) on the nitrosation of amines was also investigated. In order to draw a comparison between 0- and S-nitrosation the formation of a thionitrite in dilute aqueous acid was investigated, Alkyl nitrites have also been used in the past as nitrosating agents in non-aqueous solvents. In this thesis the kinetics of nitrosation reactions effected by an alkyl nitrite in alcohol solvent were also investigated.