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Novel difluoromethylenated [70]fullerene derivatives, C70(CF2 )n (n=1-3), were obtained by the reaction of C70 with sodium difluorochloroacetate. Two major products, isomeric C70(CF2 ) mono-adducts with [6,6]-open and [6,6]-closed configurations, were isolated and their homofullerene and methanofullerene structures were reliably determined by a variety of methods that included X-ray analysis and high-level spectroscopic techniques. The [6,6]-open isomer of C70(CF2 ) constitutes the first homofullerene example of a non-hetero [70]fullerene derivative in which functionalisation involves the most reactive bond in the polar region of the cage. Voltammetric estimation of the electron affinity of the C70(CF2 ) isomers showed that it is substantially higher for the [6,6]-open isomer (the 70-electron π-conjugated system is retained) than the [6,6]-closed form, the latter being similar to the electron affinity of pristine C70. In situ ESR spectroelectrochemical investigation of the C70(CF2 ) radical anions and DFT calculations of the hyperfine coupling constants provide evidence for the first example of an inter-conversion between the [6,6]-closed and [6,6]-open forms of a cage-modified fullerene driven by an electrochemical one-electron transfer. Thus, [6,6]-closed C70(CF2 ) constitutes an interesting example of a redox-switchable fullerene derivative.

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The structures of two bis-ethylpyrrolidinoadducts of Gd3N@I h -C80, obtained by regioselective 1,3-dipolar cycloadditions, were elucidated by single crystal X-ray, visible-near infrared (vis-NIR) spectra, studies on their thermal isomerization, and theoretical calculations. The structure of the minor-bis-adduct reveals a C 2-symmetric carbon cage with [6,6]­[6,6]-addition sites and with an endohedral Gd3N cluster that is completely flattened. This is the first example of a crystal structure of Gd3N@I h -C80 derivatives. The structure of the major-bis-adduct was inferred by the vis-NIR spectrum being corresponded to the structure of a previously reported major-bis-adduct of Y3N@I h -C80 known to have an asymmetric [6,6]­[6,6]-structure. Based on experimental results showing that the minor-bis-adduct of Gd3N@I h -C80 isomerized to the major-adduct, a possible second addition site was elucidated with support from density functional theory calculations.

Fullerene derivatives with >CH2 addends in [6,6]‐open or [5,6]‐closed configuration are uncommon of fullerene derivatives, but they are readily accessible via treatment of Cs‐C70(CF3)8 with diazomethane followed by thermolysis or photolysis. Both thermodynamic and kinetic factors favor regioselective addition of diazomethane at the near‐equatorial [5,6]‐double bond of Cs‐C70(CF3)8 to give a thermally labile pyrazoline intermediate. Thermal extrusion of N2 from the latter is a kinetically controlled process with orbital symmetry controlled Woodward–Hoffmann‐allowed mechanism. It quantitatively yields the less thermodynamically favorable [6,6]‐open isomer of C70(CF3)8[CH2] homofullerene, but the latter turns out to be capable of unexpectedly rapid quantitative phototransformation into the thermodynamically preferable [5,6]‐closed methanofullerene isomer. The transformation involves the manifold of the triplet states that facilitate the required cleavage of the Ccage–CH2 bonds.

Three Prato monoadduct isomers were synthesized and structurally characterized by 1H, 13C NMR spectra and single-crystal X-ray diffraction, and one adduct on the dd-[5,6]-bond was found as the first example of a Prato [5,6]-adduct of C70. To investigate the mechanism in the generation of this dd-[5,6]-adduct, computational studies were employed to show that it was thermodynamically obtained by sigmatropic rearrangement from the presumed initial kinetic product de-[6,6]-adduct.

The vast structural and chemical diversity of metal−organic frameworks (MOFs) provides the exciting possibility of material’s design with tailored properties for gas separation, storage and catalysis. However, after more than twenty years after first reports introducing MOFs, the discovery and control of their synthesis remains extremely challenging due to the lack of understanding of mechanisms of their nucleation and growth. Progress in deciphering crystallization pathways depends on the possibility to follow conversion of initial reagents to products at the molecular level, which is a particular challenge under solvothermal conditions. The present work introduces a detailed molecular-level mechanism of the formation of MIL-53(Al), unraveled by combining in situ time-resolved high-resolution mass-spectrometry, magic angle spinning nuclear magnetic resonance spectroscopy and X-ray diffraction. In contrast to the general belief, the crystallization of MIL-53 occurs via a solid-solid transformation mechanism, associated with the spontaneous release of monomeric aluminum. The role of DMF hydrolysis products, formate and dimethylamine, is established. Our study emphasizes the complexity of MOF crystallization chemistry, which requires case-by-case investigation using a combination of advanced in situ methods for following the induction period, the nucleation and growth across the time domain.

Stereoselective electrosynthesis of the first individual ( A)- and ( C)-1,4-fullerene derivatives with a non-inherently chiral functionalization pattern is described, as well as the first example of an optically pure protected primary amino acid directly linked to the fullerene through only the chiral α-amino-acid carbon atom. An application of an auxiliary chiral nickel-Schiff base moiety as derivatizing agent allowed separation of ( A)- and ( C)-1,4-fullerene derivatives using an achiral stationary phase, a separation which has never been done before.