Tetrathia[7]helicene ([7]TH)-based complexes substituted at the thienyl ring ends by a ferrocenyl group (Fc) or by a (η5-cyclohexadienyl)Mn(CO)3 derivative have been prepared by Sonogashira coupling reactions starting from the mono- or diiodo [7]TH compounds. The molecular structure of one of the diferrocenyl [7]TH complexes was established by X-ray analysis. Electrochemical investigation on the Fc-[7]TH systems show that the Fc groups are significantly electron poorer with respect to Fc (ΔE° ≈ 0.15 V), due to the effective conjugation of the Fc redox moiety with the triple bond + helicene system, as also confirmed by spectroscopic data. Potential cycling around the second oxidation peak, assigned to the thiahelicene moiety, affords fast, regular growth of electrodeposited conducting films, provided that one terminal α-thiophene position be available for coupling; on the other hand, long alkyl chains hamper film formation. The conducting films feature a broad oxidation wave resulting from the merging of several redox peaks, having its onset at the Fc oxidation. Since conducting films obtained by electrooligomerization of parent tetrathiahelicene have their onset potentials 0.45 V more positive than the Fc redox sites in this studied Fc-[7]TH conjugates, the above continuity could point to some coupling between Fc redox centers and conjugated π systems, favored by solid-state stacking.

Tetrathia[7]helicene-Based Complexes of Ferrocene and (η5- Cyclohexadienyl)tricarbonylmanganese: Synthesis and Electrochemical Studies / F. Rose-Munch, M. Li, E. Rose, J.C. Daran, A. Bossi, E. Licandro, P.R. Mussini. - In: ORGANOMETALLICS. - ISSN 0276-7333. - 31:1(2012), pp. 92-104. [10.1021/om200571a]

Tetrathia[7]helicene-Based Complexes of Ferrocene and (η5- Cyclohexadienyl)tricarbonylmanganese: Synthesis and Electrochemical Studies

A. Bossi;E. Licandro;P.R. Mussini
2012

Abstract

Tetrathia[7]helicene ([7]TH)-based complexes substituted at the thienyl ring ends by a ferrocenyl group (Fc) or by a (η5-cyclohexadienyl)Mn(CO)3 derivative have been prepared by Sonogashira coupling reactions starting from the mono- or diiodo [7]TH compounds. The molecular structure of one of the diferrocenyl [7]TH complexes was established by X-ray analysis. Electrochemical investigation on the Fc-[7]TH systems show that the Fc groups are significantly electron poorer with respect to Fc (ΔE° ≈ 0.15 V), due to the effective conjugation of the Fc redox moiety with the triple bond + helicene system, as also confirmed by spectroscopic data. Potential cycling around the second oxidation peak, assigned to the thiahelicene moiety, affords fast, regular growth of electrodeposited conducting films, provided that one terminal α-thiophene position be available for coupling; on the other hand, long alkyl chains hamper film formation. The conducting films feature a broad oxidation wave resulting from the merging of several redox peaks, having its onset at the Fc oxidation. Since conducting films obtained by electrooligomerization of parent tetrathiahelicene have their onset potentials 0.45 V more positive than the Fc redox sites in this studied Fc-[7]TH conjugates, the above continuity could point to some coupling between Fc redox centers and conjugated π systems, favored by solid-state stacking.
Settore CHIM/06 - Chimica Organica
Settore CHIM/02 - Chimica Fisica
Settore CHIM/01 - Chimica Analitica
Settore CHIM/03 - Chimica Generale e Inorganica
2012
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/167285
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 24
  • ???jsp.display-item.citation.isi??? 22
social impact