Selenium–nitrogen bond formation by ring expansion: synthesis of the 1,4,2-diselenazine ring system, fragmentation to a 1,2-diselenete and reactions to yield 1,4-diselenin derivatives

Abstract

1,3-Diselenolium cation salt 1 reacts with ammonia and iodine to afford the novel 1,4,2-diselenazine system 6 (40% yield) which fragments to yield dimethylcyanamide 8 and diselenin 9, presumably via intermediate 1,2-diselenete 7, which is trapped with dimethyl acetylenedicarboxylate to yield the cycloadduct 10.