Donor−Acceptor Conjugates of Lanthanum Endohedral Metallofullerene and π-Extended Tetrathiafulvalene
Citations Over TimeTop 10% of 2010 papers
Abstract
Stable donor-acceptor conjugates (2, 3) involving an endohedral metallofullerene, La(2)@I(h)-C(80), and pi-extended tetrathiafulvalene (exTTF) have been synthesized by highly regioselective 1,3-dipolar cycloadditions of exTTF-containing azomethine ylides to the endofullerene, yielding exclusively [5,6] metallofulleropyrrolidines with C(1) symmetry in high yields (68-77%). The cyclic voltammograms (CVs) of the conjugates reveal the redox active character of the system due to the presence of both donor and acceptor groups, that is, exTTF and La(2)@I(h)-C(80), respectively. Furthermore, the electrochemically reversible character of the endofullerene confirms the presence of the [5,6] adduct. Despite the relatively close proximity between the exTTF and the endohedral metallofullerene (EMF), only a weak electronic interaction was observed in the ground state, as evidenced by absorption spectroscopy and CV measurements of 2 and 3. On the other hand, in the excited state the fast formation of a radical ion-pair state (i.e., 6.0 x 10(10) s(-1)), that is, the reduction of the electron accepting La(2)@C(80) and the oxidation of exTTF, evolves with lifetimes as long as several ns (3.0 x 10(8) s(-1)) in toluene. Transient absorption spectroscopy experiments confirmed these observations.
Related Papers
- → High-resolution electron microscopy of individual metallofullerene molecules on the dipole orientations in peapods(2003)35 cited
- → Chemical derivatization of endohedral metallofullerene La@C82 with digermirane(1996)55 cited
- → Molecular and Crystal Structures(2015)2 cited
- Mass spectrometric studies of metallofullerene(2001)
- → The Endohedral Metallofullerene Y@C82.(1996)