Thirty Years of Hide-and-Seek: Capturing Abundant but Elusive M@(8)-C Isomer, and the Study of Magnetic Anisotropy Induced in Dy Ion by the Fullerene π-Ligand.

Our knowledge about endohedral metallofullerenes (EMFs) is restricted to the structures with sufficient kinetic stability to be extracted from the arc-discharge soot and processed by chromatographic and structural techniques. For the most abundant rare-earth monometallofullerene M@C, experimental studies repeatedly demonstrated (9) and (6) carbon cage isomers, while computations predicted equal stability of the "missing" (8) isomer. Here we report that this isomer is indeed formed but has not been recovered from soot using standard protocols.

A neutral diphosphene radical: synthesis, electronic structure and white phosphorus activation.

(Im)P-P(Dipp)˙ (1˙), a rare example of a neutral, mixed substituted diphosphene radical, has been prepared by reduction of (Im)PP(Dipp)[OTf] (2[OTf]) and (Im)PP(Cl)(Dipp) (3) with cobaltocene (CoCp) (Im = 4,5-dichloro-1,3-bis(1,3-diisopropylphenyl)-imidazol-2-yl, Dipp = 2,6-diisopropylphenyl). Radical compound 1˙ readily activates white phosphorus (P), resulting in the formation of an intriguing octaphosphane butterfly compound P(Im)(Dipp) (4).

Tosylazide as N1-Synthon: Iron-Catalyzed Nitrogenative Dimerization of Indoles to -Bisindolopyrazine Derivatives.

We present a straightforward one-step process to access a range of novel -diindolepyrazines via an unprecedented [-BuN][Fe(CO)(NO)] (TBA[Fe])-catalyzed intermolecular nitrogenative dimerization of various indole derivatives. Remarkably, tosylazide functions as a N1-synthon forming the central pyrazine unit that joins the two indole subunits. The catalytic transformation shows a good substrate scope, and the obtained products show interesting electronic properties.

Dimerization of a Reactive Azaacene Diradical: Synthesis of a Covalent Azaacene Cage.

Two series of regioisomeric dicyanomethylene substituted dithienodiazatetracenes with formal para- or ortho-quinodimethane subunits were synthesized and characterized. Whereas the para-isomers (p-n, diradical index y =0.01) are stable and isolable, the ortho-isomer (y =0.

Electronic Coupling in 1,2,3-Triazole Bridged Ferrocenes and Its Impact on Reactive Oxygen Species Generation and Deleterious Activity in Cancer Cells.

Mixed-valence (MV) binuclear ferrocenyl compounds have long been studied as models for testing theories of electron transfer and in attempts to design molecular-scale electronic devices (., molecular wires). In contrary to that, far less attention has been paid to MV binuclear ferrocenes as anticancer agents.

Benzo-Extended Cyclohepta[def]fluorene Derivatives with Very Low-Lying Triplet States.

Open-shell non-alternant polycyclic hydrocarbons (PHs) are attracting increasing attention due to their promising applications in organic spintronics and quantum computing. Herein we report the synthesis of three cyclohepta[def]fluorene-based diradicaloids (1-3), by fusion of benzo rings on its periphery for the thermodynamic stabilization, as evidenced by multiple characterization techniques. Remarkably, all of them display a very narrow optical energy gap (E =0.

Electrophilic Trifluoromethylation of Dimetallofullerene Anions en Route to Air-Stable Single-Molecule Magnets with High Blocking Temperature of Magnetization.

Lanthanide dimetallofullerenes with single-electron M-M bonds are an important class of single molecular magnets and qubit candidates, but stabilization of their unique electronic and spin structure in the form of a neutral molecule requires functionalization of the fullerene cage with a single radical group. The lack of selectivity of the currently available procedure results in a complicated and tedious separation process. Here we demonstrate that electrophilic trifluoromethylation of a mixture of metallofullerene anions with Umemoto reagent II is highly selective toward M@C (M = Tb, Y) anions, yielding M@C(CF) monoadducts as the main reaction product.