Molbank, Vol. 2019, Article M1090: Formaldehyde-1,1´´-(phenylphosphinidenesulfide)bis[(2S)-2-[(1R)-1-(methylamino)-ethyl]]ferrocene-aminal (Molbank)

In the course of an ongoing synthetic project, we observed an unprecedented reactivity of N-methyl groups in bis(N,N-dimethylaminoethylferrocenyl)phenylphosphinesulfide upon treatment with manganese dioxide (MnO2). The intramolecular course of this reaction resulted in the formation of an unexpected homochiral diaza macrocycle. The target structure was accessible in two steps from known N,N-dimethylaminoethylferrocene.