160558-58-7

Upstream product

• 1221-72-3 Bis(p-methoxyphenyl)diazomethan 
• 99685-96-8 fullerene-C₆₀ 
• 127349-06-8 N′-(bis(4-methoxyphenyl)-methylene)-4-methylbenzenesulfonohydrazide 

Relevant academic research and scientific papers

Electron-acceptor-induced isomerization of aryl [6,5] open fulleroids to [6,6] closed methanofullerenes and the electrochemical evaluation of their free energy difference

The thermal and photochemical rearrangements of a series of aryl substituted [6,5] open fulleroids to [6,6] closed methanofullerenes are accelerated in the presence in of electron acceptors. These [6,5] open fulleroids, facilitated by electron acceptors, rearrange thermally by a zwitteronic-type intermediate, while the photochemical reactions proceed via an excited-state electron-transfer process. The oxidation potentials of these [6,5] open fulleroids and their corresponding [6,6] closed methanofullerenes isomers have been evaluated. The free energy difference between the [6,5] open fulleroids and their corresponding [6,6] closed isomers have been estimated from the difference in their oxidation potentials.

Kinetic substituent and solvent effects in 1,3-dipolar cycloaddition of diphenyldiazomethanes with fullerenes C60 and C70: A comparison with the addition to TCNE, DDQ, and chloranil

Kinetics of 1,3-dipolar cycloaddition of a series of meta- and para-substituted diphenyldiazomethanes (DDMs) with fullerenes C60 and C70 as dipolarophiles have been investigated in toluene at 30 0°C. Fullerene C60 was ca. 1.5 times more reactive than C 70. The rate constants (k) for the primary [3 + 2] additions increased with the increase of the electron-releasing ability of the meta and para substituent. The log k/k0 values were well correlated by the Yukawa-Tsuno (Y-T) equations with the smaller negative p values (-1.6 and -1.7 for C60 and C70) and the reduced resonance reaction constants r (0.22 and 0.17) compared to similar reactions of common acceptors, TCNE, DDQ, and chloranil (CA). The plots of log k (acceptor) versus log k (C60) as reference gave good regression equations and the slopes became larger in the order of TCNE > DDQ > CA > C70 ≥ C60. The rates were also found to decrease with the increase of solvent polarity due to the ground-state solvation of fullerenes. However, the relative reactivity of these acceptors toward the unsubstituted DDM increased in the order of DDQ > C60 ≥ C70 > TCNE > CA. The unexpected higher reactivity of fullerenes was interpreted in terms of the inherent steric strain by the pyramidalization of the sp2 C-atoms as well as the shorter [6,6] bonds with larger π-electron densities.

Bis(4-methoxyphenyl)methano[60]fullerene with a methano bridge at the 6-6-ring junction

In the title compound, C75H14O2, a bis(4-methoxyphenyl)methylene group bridges a 6-6-ring junction of the C60 sphere, forming a slightly deformed cyclopropane ring. The C-C bond length involved in the cyclopropane ring fusion is 1.635 (4) A, more than 0.2 A longer than that at the 6-6-ring junction of C60. The elongation of this C-C bond leads to a slight deformation of the C60 framework, especially a shortening of two C-C bonds in equatorial positions.

Observation of both thermal first-order and photochemical zero-order kinetics in the rearrangement of [6,5] open fulleroids to [6,6] closed fullerenes

A series of [6,5] open fulleroids with radical stabilizing groups on the methano bridge were synthesized and their rearrangements to the more stable [6,6] closed fullerenes studied. These [6,5] open fulleroids all rearrange both by a zero-order photochemical process and by a higher energy unimolecular pathway involving disrotatory closure to the [6,5] closed fullerene, which subsequently rearranges to the [6,6] closed fullerene via a biradical-like intermediate.

Selective electrolytic removal of bis(alkoxycarbonyl)methano addends from C60 bis-adducts and electrochemical stability of C70 derivatives

The novel mixed his-adducts of C60, (±)-4-(±)-8 and 9, with a bis(ethoxycarbonyl)methano addend (Bingel addend) and a second addend ([1,2]benzeno, but[2]eno, methaniminomethano, or diarylmethano) bridging 6,6-closed bonds of the carbon sphere were synthesized in two-step reactions. Each bis-adduct was exhaustively electrolyzed at the potential of the second fullerene-centered reduction step, resulting in the selective removal of the Bingel addend (retro-Bingel reaction) to produce the corresponding mono-adducts, which were isolated in yields of over 60%. These results open up the possibility of using the Bingel addend as a temporary protecting and directing group in the construction of multiple adducts of C60 with unusual addition patterns. The Bingel-type mono-adduct of C70 10 and the constitutionally isomeric bis-adducts 11, (±)-12, and (±)-13 were also included in this investigation. A large difference in the electrochemical behavior between C70, bis-adducts and the corresponding C60 derivatives was observed. Thus, the intramolecular "walk-on-the-sphere" isomerization which occurs readily with Bingel-type bis-adducts of C60 under the conditions of two-electron controlled potential electrolysis (CPE) is only a minor reaction pathway in the series of C70 derivatives. The latter preferentially undergo retro-Bingel reaction.