36. "Synthesis, Structure, and Electrochemistry of an Electron-Rich Chiral Diaminoferrocene, (S,S)-Bis(2,5-dimethylpyrrolidinyl)ferrocene," Natalia F. Blank, David S. Glueck, Lev N. Zakharov,Arnold L. Rheingold, Matthew D. Saybolt, Brenna L. Ghent,and Chip Nataro, Organometallics 2005, 24, 5184-5187.

Abstract The chiral diamine (S,S)-bis(2,5-dimethylpyrrolidinyl)ferrocene (6) was prepared from diaminoferrocene and (2R,5R)-2,5-hexanediol cyclic sulfate in the presence of a base. The short C-N bond, long Fe-C(N) bond, and planar nitrogen observed in the crystal structure of 6 are consistent with efficient N-to-Cp electron donation. The resulting electron-rich metal center (with the most negative shift in redox potential yet observed for aminoferrocenes) was characterized electrochemically.