Isolation of CeLu 2 N@ I h ‐C 80 through a Non‐Chromatographic, Two‐Step Chemical Process and Crystallographic Characterization of the Pyramidalized CeLu 2 N within the Icosahedral Cage

• Published in: Chemistry : a European journal Vol. 21; no. 29; pp. 10362 - 10368
• Main Authors: Stevenson, Steven, Thompson, Hannah R., Arvola, Kristine D., Ghiassi, Kamran B., Olmstead, Marilyn M., Balch, Alan L.
• Format: Journal Article
• Language: English
• Published: 13.07.2015
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201500915

Abstract By combining two chemical methods of purification, 4 mg of purified CeLu 2 N@C 80 was readily isolated from 500 mg of carbon soot extract without the use of recycling HPLC, a method which has previously been necessary to obtain pure samples of endohedral fullerenes. In stage 1, CeLu 2 N@C 80 was selectively precipitated by virtue of its low first oxidation potential (+0.01 V) and the judicious choice of MgCl 2 as the Lewis acid precipitant. For stage 2, we used a stir and filter approach (SAFA), which employed the electron‐rich NH 2 groups immobilized on silica gel to selectively bind residual endohedrals and higher cage fullerenes that were contaminants from stage 1. Crystallographic analysis of CeLu 2 N@C 80 in the co‐crystal CeLu 2 N@ I h ‐C 80 ⋅ Ni(octaethylporphyrin) ⋅ 2(toluene) reveals that the I h ‐C 80 cage is present with a pyramidalized CeLu 2 N unit inside.