Synthesis, Spectroscopy, Electrochemistry and DFT of Electron-Rich Ferrocenylsubphthalocyanines

Abstract

A series of novel ferrocenylsubphthalocyanine dyads Y-BSubPc(H)12 with ferrocenyl-carboxylic acids Y-H = (FcCH2CO2-H), (Fc(CH2)3CO2-H) or (FcCO(CH2)2CO2-H) in the axial position were synthesized from the parent Cl-BSubPc(H)12 via an activated triflate-SubPc intermediate. UV/Vis data revealed that the axial ferrocenyl-containing ligand did not influence the Q-band maxima compared to Cl-BSubPc(H)12. A combined electrochemical and density functional theory (DFT) study showed that Fe group of the ferrocenyl-containing axial ligand is involved in the first reversible oxidation process, followed by a second oxidation localized on the macrocycle of the subphthalocyanine. Both observed reductions were ring-based. It was found that the novel Fc(CH2)3CO2BSubPc(H)12 exhibited the lowest first macrocycle-based reduction potential (−1.871 V vs. Fc/Fc+) reported for SubPcs till date. The oxidation and reduction values of Fc(CH2)nCO2BSubPc(H)12 (n = 0–3), FcCO(CH2)2CO2BSubPc(H)12, and Cl-BSubPc(H)12 illustrated the electronic influence of the carboxyl group, the different alkyl chains and the ferrocenyl group in the axial ligand on the ring-based oxidation and reduction values of the SubPcs.

Electrochemical data of ferrocenylsubphthalocyanine dyads

“…Swarts, J. Conradie, Synthesis, Spectroscopy, Electrochemistry and DFT of Electron-Rich Ferrocenylsubphthalocyanines, Molecules. 25 (2020) 2575. doi:10.3390/molecules25112575 [1] …”

“…The raw current – potential data is available in the supplementary files uploaded. The electrochemical data and CVs at a scan rate of 0.100 V s −1 , are provided in the related research article [1] . All CVs show one Fe based and one macrocycle based oxidation and two macrocycle based reductions for the four SubPcs, similar as was observed for the ferrocenylsubphthalocyanine dyads FcCH 2 OBSubPc(H) 12 [3] , FcCO 2 BSubPc(H) 12 [3] , FcBSubPc(H) 12 [4] , FcC CBSubPc(H) 12 [4] , Fc(CH 2 ) 2 CO 2 BSubPc(X) 12 and Fc(CH) 2 CO 2 BSubPc(X) 12 with X = H or F [ 2 , 5 ].…”

“…The decreasing trend of redox potential of the iron based oxidation, with increasing alkyl chain length n in Fc(CH 2 ) n CO 2 BSubPc(H) 12 (n = 0–3) is similar to the trend of the oxidation of iron in the free ferrocenylcarboxylic acids Fc(CH 2 ) n CO 2 H [6] . Reported first macrocycle based oxidation of the SubPcs generally exhibits irreversible behaviour [ 4 , 7 ], however, introduction of a ferrocenylcarboxylic acid moiety in the axial position of the subphthalocyanine L-BSubPc(H) 12 , led to chemically reversible behaviour (peak current ratios of 1) and with peak current voltage separations of Δ E < 0.092 V [ 1 , 2 , 5 ].

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“… The data presented in this paper is related to the research article entitled “ Synthesis, Spectroscopy, Electrochemistry and DFT of Electron-Rich Ferrocenylsubphthalocyanines ” [1] where electrochemical redox data and cyclic voltammograms at only a scan rate of 0.10 V s −1 of four ferrocenylsubphthalocyanine dyads Fc(CH 2 ) n CO 2 BSubPc(H) 12 (n = 0, 1 or 3) and FcCO(CH 2 ) 2 CO 2 BSubPc(H) 12 , are presented. This data article provides extensive electrochemical redox data and cyclic voltammograms at various scan rates from 0.05 up to 5.00 V s −1 to illustrate the effect of the different scan rates on the electrochemical behaviour of the four ferrocenylsubphthalocyanine dyads.…”

25th Anniversary of Molecules—Recent Advances in Inorganic Chemistry

“…On the other hand, despite its important role in biological systems and pharmaceutical applications, copper(I) can be exploited to manufacture organic light-emitting diodes (OLEDs) and light-emitting electrochemical cells (LECs), as highlighted by Meyer et al, particularly as heteroleptic complexes [ 6 ]. Similarly, iron-based ferrocenylsubphthalocyanines have been recently used to design dyads due to their tunable redox behaviour [ 7 ], while magnetite nanoparticles, when surface-functionalised with organophosphonates, allow the reversible formation and cleavage of organic bonds with high potential in switchable applications such as self-healing materials [ 8 ]. Hierarchical structures composed of materials, also called hybrid materials, may address specific environmental issue such as wastewater treatment; da Silva et al report the development of Fe alloys and Fe-oxides dispersed in mesoporous matrixes that provide new nanodispersed materials able to adsorb organic molecules (mainly dyes) present in wastewater followed by magnetic separation [ 9 ].…”