Ring Ions in the Ion Chemistry of Thiirane, Ethanediol-1,2, Ethanedithiol-1,2 and 2-Mercaptoethanol

Abstract

The molecular ion of thiirane retains the ring structure of the neutral molecule during ionization with great probability [1,2]. The same is true for phosphirane [3]. The three-ring heterocycles C₂H₄X (X = N,O) containing the lighter elements of group V and VI react different. The oxirane molecular ion ring-opens before reaction with n-donor bases[4]. Aziridine has no ion chemistry characteristic for its structure at all [2]. The cyclopropane molecular ion [5,6] shows ion-molecule reactions indicating three equivalent carbon atoms. The tendency to form rings is quite pronounced in ion chemistry of the sulfur containing compounds 2-mercaptoethanol and ethane-dithiol-1,2. The same is found for the oxygen analogue ethanediol-1,2. Among the most abundant product ions in the ion chemistries are cyclic acetals or ketals and thioacetals or thioketals, respectively.