Mass spectra of 3,6-dihalo-4,4-dimethyl-l,4-seIenasilafulvenes and 2,4-dihalo-2-dihalomethyl-3,3-dimethyl-l-selena-3-silacyclopent-4-enes

摘要

The behavior of new heterocyclic systems,viz.,3,6-dihalo-4,4-dimethyl-l,4-selena-silafulvenes la,b and 2,4-dihalo-2-dihalomethyl-3,3-dimethyl-l-Selena-3-silacyclopent-4-enes 2a,b (Hal=Cl,Br),was studied under conditions of electron ionization and thermal decomposition.Their fragmentation is accompanied by skeletal rearrangements,and the positive charge is localized mainly on ions containing silicon.Selenasilafulvenes la,b form stable molecular ions.Selenasilacyclopent-4-ene 2a decomposes partially and compound 2b decomposes completely in the gas phase with the elimination of a hydrogen halide and a halogen molecules.