1,4-Fullerenols C₆₀ArOH: Synthesis and Functionalization

Abstract

A mild and facile process for the preparation of 1,4-fullerenols C(60)ArOH was achieved. The key intermediate 1,2-C(60)Ar(NO(2)) was identified to better understand the reaction mechanism. Further functionalizations including esterification, etherification, and arylation of the synthesized 1,4-C(60)ArOH provided efficient access to versatile fullerene derivatives in the presence of p-toluenesulfonic acid.

Design Concept for High-LUMO-level Fullerene Electron-acceptors for Organic Solar Cells

“…+ intermediate (Scheme 1); 20 2) reaction of C 60 with arylhydrazine and sodium nitrite producing 1,4-C 60 Ar(OH), 21 which react with arenes in the presence of p-toluenesulfonic acid giving 1,4-C 60 Ar 2 (Scheme 2); 22 3) hydroarylation reaction of C 60 in the presence of trichloroaluminum and a small amount of water giving C 60 Ar 2 H 2 , 23 which is deprotonated by base, followed by oxidation of the resulting fullerene anions by copper(I) salt to produce 1,4-C 60 Ar 2 (Scheme 3); 24 4) rhodiumcatalyzed addition reaction of arylboronic acids to C 60 producing monoadducts C 60 ArH, 25 which undergo palladium-catalyzed cross-coupling reaction with aryl halide to obtain 1,4-C 60 Ar 2 (Scheme 4). 26 Although diarylfullerene is a stable compound, its performance as an electron-acceptor in organic thin-film solar cells is limited.…”

1,4‐Fullerene Derivatives: Tuning the Properties of the Electron Transporting Layer in Bulk‐Heterojunction Solar Cells

“…The synthesis of the novel 1,4‐adducts reported herein was achieved by Wang and co‐workers by reaction of 1,4‐fullerenol with a variety of different aromatic substituents 10. The procedure developed for the synthesis of the addends was to react the 1,4‐aryl fullerenol with a substituted benzene, used as the solvent of the reaction, and in the presence of p ‐toluene sulfonic acid (TsOH) 10a. The identity of the 1,4‐fullerene addends was confirmed by 1 H‐ and 13 C‐NMR spectroscopy (the latter displayed more than 40 signals for the sp 2 carbons on the fullerene, which is consistent with C 2 symmetry) as well as mass spectrometry.…”

Dramatic Mechanistic Change in Acid‐Catalyzed Arylation of Azafulleroids Depending on their Ambident N/C Basicity: Formation of Cyclopentene Centered Pentakisadduct

“…So far, such cross arylation has been achieved via relatively stable 1,4-arylfullerenols. [13] Therefore, practical stability of monoarylated 2 a-e can be ascribed to the less facile leaving group of protonated butylamine than tosyl amine.…”

“…6 showed multiplet 3H peaks at 4.6-4.7 ppm, and 13 C NMR indicated Cs symmetry of fullerene sphere with ca. 30 sp 2 peaks (along with 6 peaks of o-xylene) and five sp 3 peaks.…”

“…For alkylazafulleroid 1 a (R = (CH 2 ) 3 COOMe, path a), the ammonium ion A by the protonation of nitrogen suffers the cleavage of one bridged enamine C À N bond and the [5,6] ring closure to generate fullerenyl cation B. [13,19] The nucleophilic attack of aromatic compounds preferably occurs at the less hindered para-position [9,10,12,13] to afford 1,4-monoarylated aminofullerenes 2 a-e. However, benzylazafulleroids 1 b,c (R = CH 2 Ar) become tetrahydroisoquinolinofullerenes 5 b,c via an intramolecular nucleophilic cyclization of the corresponding fullerenyl cation B at the adjacent orthocarbon.…”