Gaseous Carbonium Ions from the Decay of Tritiated Molecules

Abstract

This chapter discusses information on solution chemistry of carbonium ions, and extensive and sophisticated research on their role as intermediates in a variety of organic reactions. The mass spectrometer has gradually developed into a versatile and sophisticated tool for the study of ion-molecule reactions, and provided most of the information at present available on the chemistry of gaseous carbonium ions. A promising approach for introducing carbonium ions of known structure into gaseous systems at any desired pressure, and for studying their reactions by the usual methods of physical organic chemistry, including the isolation and the analysis of the final products, is provided by a technique based on a nuclear transformation. A number of experimental investigations, carried out with specially developed mass spectrometric techniques, confirmed and extended the theoretical predictions, and demonstrated the actual formation of carbonium ions from the decay of T atoms contained in simple organic molecules. The results obtained from the study of the reactions of carbonium ions directly formed from the decay of tritiated molecules in organic systems at normal pressure. The chapter also deals with the reactions of the carbonium ions formed from the protonation of organic substrates with a very strong Brøsted acid, the helium tritide molecular ion, obtained from the 8-decay of molecular tritium.