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A layered graphitic material was prepared from an alkyne-containing, reactive molecular precursor at low temperature without catalyst. The resulting nanomaterial is made of stacks of a few partially graphitized nanosheets and is soluble in common organic solvents in which it exhibits green fluorescence.

Rational design of meta-linked oligophenylbutadiynylene (OPBD) derivatives was conducted in order to gain insight into their gelation properties and reactivity toward topochemical polymerization to yield polydiacetylenes (PDAs). Different structural parameters influencing the gel formation such as the presence of peripheral 2-hydroxyethoxy side chains and the position of amide functionalities, responsible for intermolecular hydrogen bonds, were studied. Topochemical polymerization of butadiyne units contained within the OPBDs was performed and the resulting PDAs were characterized by electron microscopy and spectroscopy.

A star-shaped molecule with three butadiyne moieties attached to a central phenyl core was self-assembled via organogel formation in different solvents and subjected to UV irradiation in its xerogels form to give a soluble conjugated 1D nanowire made of three connected polydiacetylene (PDA) chains. The resulting polymer has a slightly lower optical band gap than its linear counterpart and presents no chromism property, indicative of the rigid nature of the polymer thus obtained.

Soluble organic nanorods were prepared from phenylacetylene macrocycles using the topochemical polymerization of butadiyne moieties placed both inside and outside the macrocycles' skeletons. Macrocycles containing amide groups were self-assembled in a columnar fashion through the formation of an organogel in ethyl acetate. Upon irradiation with UV light, the Raman signals associated with butadiyne units completely vanished, indicating the creation of covalently linked nanorods.

A diarylbutadiyne derivative was synthesized using a few steps and gelified in aromatic solvents. The gel prepared at low concentration is made of micrometers-long nanofibrils as shown by scanning electron microscopy. XRD of the dried gel shows sharp features, revealing a well-organized material. A topochemical reaction was performed on the dried gel, and a polydiacetylene presenting reversible thermochromism properties was obtained.

Rigid organic nanotubes were prepared from six-membered phenylene-butadiynylene macrocycles through topochemical polymerization in the xerogel state. All six butadiyne units underwent polymerization, thus creating rigid nanotubes with six polydiacetylene chains lying parallel, one relative to each other.

Carbon nanoparticles were obtained at room temperature by irradiating an organogel made from a 1,8-diaryloctatetrayne derivative in chloroform. During the topochemical polymerization, the morphology of the gel changes from fibers to soluble, yellow fluorescent nanoparticles in high yield. Analyses suggest that the resulting nanoparticles are made of amorphous graphitic carbon.

An amide-containing phenylacetylene macrocycle (PAM) has been synthesized and its gelation properties were studied in different solvents. Surprisingly, this macrocycle forms organogels at low concentration in many polar and apolar solvents. XRD and FTIR analysis suggest that this macrocycle forms stable supramolecular assemblies owing to H-bonding. Scanning electron microscopy analyses show the formation of bundles of nanofibrils, demonstrating the long-range organization of this material.

Pyrolysis of polydiacetylene-walled nanorods obtained from a rigid and shape-persistent macrocyclic precursor was performed. The thermogravimetric analysis showed that pyrolysis caused a loss of aliphatic chains and structural changes of PDAs to produce carbon-rich nanoarchitectures, as confirmed by Raman and UV-visible spectroscopy. The transmission electron microscopy imaging performed on the resulting material showed the formation of an entangled nanofibrils network containing various types of nanostructures.

Two series of amide-containing phenylacetylene macrocycles (PAMs) were prepared and self-assembled through a gelation process in an organic solvent. Their gelation properties along with their molecular arrangements in the xerogel state, their morphological features and their reactivity toward the topochemical polymerization of the butadiyne units embedded within the structure were studied with respect to the amide configuration. The PAMs of series 1 with the nitrogen atom of the amide function directly attached to the phenyl groups of the PAMs (acetanilide derivatives) showed less organized molecular organization and less reactivity toward topochemical polymerization than the PAMs of series 2 with the inverted amide configuration (benzamide derivatives). The importance of the amide configuration in the gelation process was confirmed by theoretical calculations at the density functional theory level. Moreover, the computed architecture for molecules of series 1 was shown to be incompatible with topochemical reaction in agreement with experimental observation. The actual combination of experiments and calculations allows the design of larger covalently linked, rigid organic nanotubes.