Preparation, characterization and properties of dipolar 1,2-N,N-dimethylaminomethylferrocenylsilanes

A series of substituted 1,2-N,N-dimethylaminomethylferrocenyl compounds were synthesized and characterized by 1H-NMR, 13C-NMR, 29Si-NMR, ES–MS, IR, UV–vis and 57Fe-Mössbauer spectroscopy. The new (R,S)-2-(N,N-dimethylaminomethyl)ferrocenyl-(aryl)silanes (R,S)-FcNSiMen(C6H4X)m (n=2–0, m=1, X=p-F (5); m=2, X=p-F (6); m=3, X=p-F (7) and m=1, X=p-Br (14) were formed by the reaction of 2-dimethylaminomethylferrocenyllithium FcNLi (1) with chloroarylsilanes ClSi(Me)n(C6H4X)m (n=2–0, m=1, X=p-F (2); m=2, X=p-F (3); m=3, X=p-F (4) and m=1, X=p-Br (13)). The treatment of 5, 6 and 14 with gaseous hydrogen chloride or picric acid resulted in the formation of the hydrochloride complexes 9, 10, 15 and the picrates 11, 12 and 16. The treatment of 14 with LiR or Mg and DMF resulted in the formation of (R,S)-2-(N,N-dimethylaminomethyl)ferrocenyl(4-formylphenyl)dimethylsilane (18). The crystal structures of 7, 12 and 15 were determined by single crystal X-ray analyses. 57Fe-Mössbauer spectroscopy gives evidence of a significant electronic coupling between the ferrocenyl unit and the organic acceptor moiety of the molecules in the ground state.