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[60]Fullerene was functionalized with a mesomorphic malonate derivative containing two ferrocene units; the targeted compound showed thermotropic liquid-crystalline properties.

The synthesis and the liquid crystalline properties of a new class of conjugated derivatives that assembled four oligophenylenevinylene (OPV) moieties arising from a calix[4]arene core are described. Photophysical investigations also revealed strong electronic coupling between the four OPV fragments of the calix[4]OPV derivative.

Amphiphilic fullerene bis-adducts 11 and 14 containing two and four cholesterol moieties, respectively, were prepared starting from the corresponding bis-malonate derivatives. In a systematic study, their spreading behavior at the air-water interface was compared to that of bis-adduct 6 with no polar head-group. Compared to 6, for which some three-dimensional aggregation occurs, the polar head-group in 11 and 14 is responsible for an attractive interaction with the aqueous subphase, forcing the molecules towards the water surface into a twodimensional arrangement. Even if homogeneous Langmuir films were obtained with both 11 and 14, only the films of 14 show a reversible compression/expansion behavior. This suggests that, by increasing the number of cholesterol subunits, the encapsulation of the C-sphere in its addend is more efficient, thus preventing fullerenefullerene interactions and aggregation phenomena. The Langmuir films of 11 and 14 were also efficiently transferred onto hydrophilic quartz slides, yielding Langmuir-Blodgett films.

Grafting of a ferrocene-con- taining liquid-crystalline malonate de- rivative to C60 led to the mixed full- erene - ferrocene material 1 which gave rise to a smectic A phase. Cholesterol was used as liquid-crystalline promoter. X-ray diffraction experiments and volu- metric measurements indicated that 1 is organized in double layered structures. The corresponding supramolecular or- ganization within the mesomorphic la- mellar phase is characterized by a micro- segregation of the different units (ferro- cene, fullerene, and cholesterol) in distinct sublayers. In such a smectic A phase, C60 imposes the arrangement of the other molecular moieties. Photo- physical studies revealed that electron transfer occurs from the donor ferrocene to the electron accepting fullerene. The formation of a long-lived radical pair, with lifetimes of the order of several hundred nanoseconds, was confirmed by time-resolved spectrometry, especially in the near infrared region, in which the radical anion of the fullerene moiety displays its characteristic fingerprint ab- sorption.

Functionalization of C60–oligophenylenevinylene derivatives with a cyanobiphenyl-terminated dendromesogen leads to new donor–acceptor systems with liquid-crystalline properties.

Addition of liquid-crystalline dendrimers onto [60]fullerene led to thermotropic liquid crystals which displayed various types of mesophases, including chiral nematic, smectic B, smectic A and columnar phases. This approach represents an interesting way for the design of self-organized structures based on [60]fullerene, and opens the way to optoelectronic applications for this carbon allotrope, such as for the development of photovoltaic devices and molecular switches.

Due to their high and variable coordination numbers leading to poorly predictable three-dimensional coordination spheres, the trivalent lanthanide metal ions are challenging molecular objects for introduction into thermotropic liquid crystals. Conversely, their predictive electronic, optical and magnetic metal-centred properties make them particularly attractive for being incorporated into switchable macroscopic materials responding to external electric and magnetic stimuli. We briefly describe here some of the important concepts and strategies leading to the recent successful preparation of luminescent thermotropic lanthanide-containing mesophases, for which the generic term lanthanidomesogens is proposed.

A series of bromoalkyloxy-substituted terphenylenes were synthesized through a Palladium cross-coupling reaction between arylboronic acids and bromoaryl derivatives. By DSC it was observed that the...

[structure: see text] [60]Fullerene was functionalized with a TTF derivative and a bis-mesogenic fragment. The synthetic methodology was based on the addition of a malonate derivative to C60 (Bingel-type reaction). Both the malonate and dyad showed smectic B and A phases. The supramolecular organization within the smectic layers was of the monolayer type for the malonate and of the bilayer type for the fullerene derivative. In the latter case, the supramolecular organization was governed by the C60 unit.

An oligophenylenevinylene-benzocrown ether conjugate has been prepared and its binding selectivity for alkali metal ions evaluated by electrospray mass spectrometry. Whereas this benzocrown-ether derivative does not exhibit any liquid crystalline properties, the self-assembly by coordination to potassium or cesium leads to supramolecular sandwich complexes with mesomorphic properties.