Flash Communication: Synthesis, Structural Characterization, and Reactivity of a Selenazolidine and a 1,3-Tetrahydroselenazine that Bear a Pentafluorophenyl Substituent

The synthesis, structural characterization in the solid state, and reactivity of a selenazolidine and a six-membered-ring derivative, i.e., a 1,3-tetrahydroselenazine, that contain a C6F5 substituent are reported. The first crystallographic characterization of a 1,3-tetrahydroselenazine was accomplished by means of single-crystal X-ray diffraction analysis. Despite the structural analogy to C6F5-substituted imidazolidines, these selenium-containing heterocycles exhibit pronounced thermal stability and high resistance toward the formation of the corresponding (amino)(seleno)carbenes, highlighting fundamentally different reactivity patterns between imidazolidines and selenazolidines.