Selenium-containing heterocycles from isoselenocyanates: Synthesis of 1,3-selenazinane and 1,3-selenazinanone derivatives

摘要

The reaction of the intermediate ketene N,Se-hemiacetal 3, prepared from cyanomethylene derivatives 1 by treatment with Et3N and aryl isoselenocyanates 2, with bis-electrophiles 6, 7,9, and 11 in DMF affords tetrahydro-1H-1,3-selenazine (= 1,3-selenazinane) derivatives 8, 10, and 12 in good yield (Scheme 2 and Tables 1-3). Chemical and spectroscopic evidence for the structures of the new compounds are described. The structures of 8d and 12e are established by X-ray crystallography (Figs. 1 and 2).