TY - JOUR
T1 - Multistep redox processes and intramolecular charge transfer in ferrocene-based 2,2′-bipyridylboronium salts
AU - Fabrizi De Biani, Fabrizia
AU - Gmeinwieser, Thomas
AU - Herdtweck, Eberhardt
AU - Jäkle, Frieder
AU - Laschi, Franco
AU - Wagner, Matthias
AU - Zanello, Piero
PY - 1997/10/28
Y1 - 1997/10/28
N2 - A one-step high-yield synthesis of donor-acceptor complexes [IA]X to [ID]X, [2A]X2, and [4A]X4 with one, two, and four cationic [B(R)bipy]+ acceptors (R = Me, Br, OEt, NC4H8; X = Br, PF6; bipy = 2,2′-bipyridine) covalently attached to a ferrocene donor is described. Apart from 2,2′-bipyridine, 1,10-phenanthroline and 2,2′-bipyrimidine have also been used as chelating amines. With the exception of R = Br, water-stable compounds are obtained in all cases. In DMF solution and under an inert atmosphere, [1A]PF6, [2A](PF6)2, and [4A]-(PF6)4 behave as reversible three-step redox systems, capable of storing three, five, and nine electrons, respectively. In their cationic state, the complexes possess an intense purple color, which can be attributed to charge-transfer interactions between the ferrocene unit and the electron-poor B(R)bipy substituent(s). This is confirmed by the ESR spectrum of the monoreduced species [1A]○, which features a line shape indicating considerable admixture of the ligand and metal orbitals.
AB - A one-step high-yield synthesis of donor-acceptor complexes [IA]X to [ID]X, [2A]X2, and [4A]X4 with one, two, and four cationic [B(R)bipy]+ acceptors (R = Me, Br, OEt, NC4H8; X = Br, PF6; bipy = 2,2′-bipyridine) covalently attached to a ferrocene donor is described. Apart from 2,2′-bipyridine, 1,10-phenanthroline and 2,2′-bipyrimidine have also been used as chelating amines. With the exception of R = Br, water-stable compounds are obtained in all cases. In DMF solution and under an inert atmosphere, [1A]PF6, [2A](PF6)2, and [4A]-(PF6)4 behave as reversible three-step redox systems, capable of storing three, five, and nine electrons, respectively. In their cationic state, the complexes possess an intense purple color, which can be attributed to charge-transfer interactions between the ferrocene unit and the electron-poor B(R)bipy substituent(s). This is confirmed by the ESR spectrum of the monoreduced species [1A]○, which features a line shape indicating considerable admixture of the ligand and metal orbitals.
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U2 - 10.1021/om970345z
DO - 10.1021/om970345z
M3 - Article
AN - SCOPUS:0006632692
SN - 0276-7333
VL - 16
SP - 4776
EP - 4787
JO - Organometallics
JF - Organometallics
IS - 22
ER -