Reaction of 2,6-xylyl isoselenocyanate with organolithium compounds

Reaction of 2,6-xylyl isoselenocyanate (1) with organolithium compounds was examined focussing on the siteselectivities. Phenyllithium attacked selenium exclusively whereas some benzylic organolithiums reacted at the central carbon of 1 to afford the corresponding lithium selenocarboximidates. Phenylethynyllithium and (t)BuLi gave mixtures of the carbophilic and selenophilic products. The lithium enolate of isobutyrophenone reacted with 1 at both its C- and O-nucleophilic centers attacking the central carbon of 1. By the alkylation of lithium selenocarboximidates formed from 1 and benzylic organolithiums, several selenoimidates were synthesized. Copyright (C) 1996 Elsevier Science Ltd