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• 1271-48-3 1,1'-ferrocenyldicarboxaldehyde 
• 13214-66-9 4-phenyl-1-butylamine 

Relevant academic research and scientific papers

Aminomethyl-substituted ferrocenes and derivatives: Straightforward synthetic routes, structural characterization, and electrochemical analysis

A variety of aminomethyl-substituted ferrocenes and the parent compounds (iminomethyl)ferrocenes, azaferrocenophanes, and diferrocenylamines can be selectively synthesized from reductive amination of 1,1′-diformylferrocene or formylferrocene. The optimized one- or two-step reactions have delivered 13 new compounds, isolated in 65-97% yields, which include tertiary (ferrocenylmethyl)amines and azaferrocenophanes by using NaBH(OAc)3 as a mild reducing agent and (iminomethyl)ferrocenes and secondary (ferrocenylmethyl)amines by using LiAlH4. X-ray structures of representative members of these ferrocene derivative families have evidenced the preferred conformation adopted by ferrocene backbones, in which surprisingly the steric hindrance is apparently not systematically minimized. 15N NMR measurements on aminomethyl-substituted ferrocenes and derivatives are provided for the first time, establishing benchmark values ranging from -330 to -305 ppm (nitromethane δ 0 ppm). The cyclic voltammetry of these species evidences two clearly distinct oxidation potentials related to the iron(II) center and the amino function. These aminomethyl-substituted ferrocenes are potentially valuable for further ortho-directed functionalization of ferrocene.

Further investigation on preparation, structure and electrochemical properties of N-alkyl- and N-aryl-2-aza-[3]-ferrocenophanes

The reactions of 1,1′-bis(hydroxymethyl)ferrocene with amines primary atnines such as 6-aminohexanol, cyclohexylamine, 4-phenylbutylamine, 2-isopropylaniline, 4-(trifluoromethyl)benzylamine, and 1-aminomethylferrocene in the presence of [RuCl2(PPh3)3] catalyst led to intermolecular condensation of the CH2OH and NH2 groups to afford N-alkyl- or N-aryl substituted 2-aza-[3]-(1,1′)-ferrocenophanes. Cyclic voltammograms of the obtained N-alkyl-2-aza-[3]-(1,1′)-ferrocenophanes exhibit reversible redox of the Fe center at E1/2 = -0.01 - +0.04 V (vs Ag+/Ag) and subsequent irreversible oxidation of the amino group of the ligand at Eox = 0.41-0.44 V. N-(4-Hydroxyphenyl)-2-aza-[3]-(1,1′)-ferrocenophane shows two pairs of reversible electrochemical oxidation and reduction at E1/2 = 0.04 and 0.44 V. The latter potential is significantly lower than the corresponding electrochemical oxidation of N-aryl-2-aza-[3]-(1,1′)-ferrocenophanes (0.68-0.75 V). The N-alkyl-2-aza-[3]-(1,1′)-ferrocenophanes react with MeI to cause methylation of the amino group to produce cationic 2-aza-[3]-(1,1′)-ferrocenophanes containing a quaternary nitrogen center. The iodo counter anion is easily replaced with BF4- or PF6-. Cyclic voltammograms of the cationic ferrocenophanes show the redox between ferrocene and ferrocenium at E1/2 = 0.37-0.42 V.