Synthetic approach to skeletally diverse nitrogen heterocycles from dicyano-2-methylenebut-3-enoates†
Abstract
The [2 + 1], formal-[4 + 1] and [5 + 1] annulations of electron-deficient dienes with ambiphilic nitrogen reagents were developed on the basis of a similar vinylogous aza-Michael addition. These synthetic approaches enable the divergent synthesis of several interesting heterocyclic skeletons, such as vinylaziridines, pyrroline and 2-aminopyridines, from easily accessible starting materials under mild conditions.