207797-73-7Relevant articles and documents
Electrochemical reduction of some [(η5-Cyclopentadienyl) (η6-arene) iron(II)][PF6] complexes bearing an imine or a nitrone function in benzylic position of the arene ligand
Pierre, Fabrice,Stricker, Andrea,Moinet, Claude,Sinbandhit, Sourisak,Toupet, Loic
, p. 253 - 267 (2007/10/03)
The electrochemical reduction in basic hydro-organic media of mixtures of [(η5-Cp) (η6-benzophenone-N-(aryl)nitrone) Fe]+ 1a-d and [(η5-Cp) (η6-benzophenone anil) Fe]+ complexes 1′a-d led to the corresponding [(η5-Cp) (η6-α-(arylamino)diphenylmethane) Fe]+ cations 2a-d with good yields (85-90%). In a similar manner, various [(η5-Cp) (η6-9-(arylamino)fluorene) Fe]+ cations 4a-i were synthesized (70-88% yield) in acidic hydro-organic media from the corresponding [(η5-Cp) (η6-fluorenone anil) Fe]+ 3a-i or the [(η5-Cp) (η6-fluorenone-N-(2′-methoxycarbonyl phenyl)nitrone) Fe]+ derivative 3′i. According to 1H NMR chemical shifts, the exo isomer is formed in the majority (exo:endo ca. 75:25) during electrosynthesis of compounds 4a-i. We could explain these unexpected results by an epimerization in the electrolysis media. The amines 4a,b were re-oxidized by oxygen into the starting imine 3a,b under very mild Al2O3-catalysis conditions (77-80% yield).