Tatsuaki Sakano

N-Substituted 2-aza-[3]-ferrocenophanes. New synthesis using RuCl2(PPh3)3 catalyzed condensation, structure, and electrochemical behavior

Abstract The reactions of 1,1′-ferrocenedimethanol with arylamine and with alkylamine in the presence of RuCl 2 (PPh 3 ) 3 catalyst led to condensation of CH 2 OH and NH groups to afford N -alkyl-(or N -aryl-)2-aza-[3]-ferrocenophanes. The 1 H- and 13 C-NMR spectra and crystallography of N -(4-butylphenyl)-2-aza-[3]-ferrocenophane showed the proposed structure. Electrochemical oxidation of the N -aryl- and N -alkyl-2-aza-[3]-ferrocenophane was studied.

Preparation and characterization of various N-substituted-2-aza-[3]-ferrocenophanes and their chemical and electrochemical properties

Abstract RuCl2(PPh3)3 catalyzed condensation of 1,1′-ferrocenedimethanol with primary amines afforded N-alkyl- or N-aryl-2-aza-[3]-ferrocenophanes which were characterized by 1H and 13C NMR spectra. X-ray crystallography of N-(4-butylphenyl)-2-aza-[3]-ferrocenophane unequivocally revealed its mononuclear structure. The N–C (aryl) bond distance is shorter than the N–CH2 single bond due to extension of π-conjugation of the aromatic ring to the nitrogen atom. N-Hexyl-2-aza-[3]-ferrocenophane reacts with methyl iodide to give the N-methylated product which was characterized by NMR spectroscopy and X-ray crystallography. N-Aryl-2-aza-[3]-ferrocenophanes exhibited reversible redox between ferrocene and ferrocenium cations and an irreversible oxidation peak at a higher oxidation potential.

Polyacetylenes with Ferrocenophane Pendant Groups: Synthesis by Rh‐Complex‐Catalyzed Polyaddition, Characterization and Properties

The Rh(I)-complex-catalyzed polymerization of N-(4-propynyloxyphenyl)-2-aza-[3]-ferrocenophane (1) and of N-(4-pentynyloxyphenyl)-2-aza-[3]-ferrocenophane (2) gives the corresponding polyacetylenes with ferrocenophane pendant groups: compounds 3 and 4, respectively. Polymers 3 and 4 are soluble in organic solvents such as tetrahydrofuran and CHCl 3 , although polymer 3 contains a small portion of an insoluble fraction. The molecular weights of polymers 3 (soluble part) and 4 are determined to be M n = 10 000 and M w = 14 000, and M n = 5 100 and M w = 9 300, respectively. The copolymerization of 1 and 4-ethynyltoluene yields copolymers containing the two monomer units in various ratios depending on the ratio of the monomers used in the polymerization. Molecular weights of the copolymers range from M n = 8 800 and M w = 13 200 to M n = 23 800 and M w = 36 900, and increase with a decreasing content of monomer units derived from 1. The thermal decomposition temperature is also influenced linearly over a wide range by the monomer unit ratios. All these polymers are characterized by NMR and UV spectroscopies as well as by elemental analyses. The polymers undergo two electrochemical oxidations: quasi-reversible oxidation of the Fe and irreversible oxidation of the nitrogen-containing part of the ferrocenophane unit. Cyclic voltammograms of 4 cast on a Pt plate in MeCN solution of NEt 4 BF 4 .