Novel anionic oligomerization by a new, sequential generation of organolithium compounds

Anionic polymerizations (oligomerizations) are mainly divided into two classes depending on how the organometallic initiator is added to the monomeric substrates: the two-carbon propagations of most reactions and the multiple 1,4-addition of carbanions to conjugate dienes. Currently unknown is the one-carbon propagation in the anionic polymerization, which is categorized into the third, hitherto unexplored class of anionic polymerization (oligomerization). In this paper, it is shown that the anionic oligomerization of arylaziridine hydrazones of aldehydes can be effected under the influence of catalytic amounts of organolithium compounds to give oligo(alkylidene) s.