Structure and fragmentations of [C 3 H 7 S] + ions

The principal fragmentation reactions of metastable [C 3 H 7 S] + ions are loss of H 2 S and C 2 H 4 . These reactions and the preceding isomerizations of [C 3 H 7 S] + ions with six different initial structures were studied by means of labelling with 13 C or D. From the results it is concluded that the loss of H 2 S and C 2 H 4 both occur at least mainly from ions with the structure [CH 3 CH 2 CHSH] + or from ions with the same carbon sulfur skeleton, with the exception of the ions with the initial structure [CH 3 CH 2 SCH 2 ] + , which partly lose C 2 H 4 without a preceding isomerization. For all ions, more than one reaction route leads to [CH 3 CH 2 CHSH] + . It is concluded that the loss of H 2 S is at least mainly a 1,3‐elimination from the [CH 3 CH 2 CHSH] + ions. Both decomposition reactions are preceded by extensive but incomplete hydrogen exchange.