GENERATION OF 1,3-DITHIA-2-TELLUROLE, 1-SELENA-3-THIA-2-TELLUROLE, AND 1,3-DISELENA-2-TELLUROLE BY NEUTRALIZATION-REIONIZATION MASS-SPECTROMETRY

2,2-Dichloro-1,3-dichalcogena-2-telluroles of sulfur and selenium, C6H 4[XTe(Cl)(2)Y] with X, Y = S, Se, serve as precursors to generate the cation radicals of 1,3-dichalcogena-2-telluroles C6H4[XTeY](+.) corres ponding neutral counterparts by means of neutralization-reionization m ass spectrometry. These neutral 2-telluroles are intrinsically stable for at least 1 mu s in the gas phase. The most abundant fragmentation channel at the neutral and cationic stages is due to loss of atomic te llurium to afford the corresponding benzo-1,2-dichalcogena-cyclobutene s. For the latter, partial isomerization to the related dichalcogena-o rtho-quinones is indicated by the mass-spectrometric fragmentation pat tern.