Harnessing Electron Transfer from the Perchlorotriphenylmethide Anion to Y@C82(C2v) to Engineer an Endometallofullerene-Based Salt

6 pages, 5 figures, 1 schemeWe show that electron transfer from the perchlorotriphenylmethide anion (PTM−) to Y@C82(C2v) is an instantaneous process, suggesting potential applications for using PTM− to perform redox titrations of numerous endohedral metallofullerenes. The first representative of a Y@C82-based salt containing the complex cation was prepared by treating Y@C82(C2v) with the [K+([18]crown-6)]PTM− salt. The synthesis developed involves the use of the [K+([18]crown-6)]PTM− salt as a provider of both a complex cation and an electron-donating anion that is able to reduce Y@C82(C2v). For the first time, the molar absorption coefficients for neutral and anionic forms of the pure isomer of Y@C82(C2v) were determined in organic solvents with significantly different polarities.This work was supported in part by the Spanish Direcci ón General de Investigació n (DGI; project POMAs, CTQ2010-19501/BQU), the Generalitat de Catalunya (2009SGR00516), the bilateral CSICNFBR project 2008RU0073, the RFBR (09-03-91291-INIS-a and 13- 03-01291-a), the Presidium of the RAS (program no. 8), and the European project ERC StG 2012-306826 e-GAMES. E.L. thanks CIBER-BBN, an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Peer reviewe

Spin-transfer complexes of endohedral metallofullerenes: ENDOR and NMR evidences

The aim of this research was to answer the question whether the area of localization of unpaired electron in a paramagnetic endohedral metallofullerene is restricted by the fullerene shell or a “spin-leakage” beyond the fullerene cage is possible. Herein, we report an ENDOR investigation of La@C₈₂ embedded into the polycarbonate films. The intensive ¹H-ENDOR signal has been revealed. Since the La-EMF does not contain hydrogen atoms, this result testifies to the contact hyperfine interaction of the unpaired electron of La-EMF with the matrix hydrogen atoms, i.e. electron spin density on the polymer protons. We also report a NMR investigation of a liquid solution of the same La-EMF in hexamethylphosphoramide (HMPA), molecules of which contain the NMR active nucleus, phosphorus-31. The paramagnetic shift of the ³¹P NMR signal of bulk HMPA molecules in the presence of La-EMF has been revealed. Thus, much as the charge-transfer complexes, the paramagnetic EMF molecules can form the spin-transfer complexes in which the electron spin density partially localizes beyond the fullerene cage on atoms of the matrix in which the EMF molecules are embedded