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.

Oxygen causes food spoilage and drug degradation, which is addressed commercially by modified atmosphere packaging. We report herein a wireless oxygen sensor, O-p-CARD, from solution processed Fe-poly(4-vinylpyridine)-single-walled carbon nanotube composites on commercial passive near-field communication tags. A large irreversible attenuation in the reflection signal of an O-p-CARD was observed in response to oxygen at relevant concentrations, enabling non-line-of-sight monitoring of modified atmosphere packaging. These devices allow for cumulative oxygen exposure inside a package to be read with a conventional smartphone. We have demonstrated that an O-p-CARD can detect air ingress into a nitrogen-filled vegetable package at ambient conditions. This technology provides an inexpensive, heavy-metal-free, and smartphone-readable method for in situ non-line-of-sight quality monitoring of oxygen-sensitive packaged products.

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.

New anthanthrone-based polycyclic scaffolds possessing peripheral crowded quinodimethanes have been prepared. While the compounds adopt a closed-shell butterfly-shaped structure in the ground state, a curved-to-planar fluxional inversion is accessible with a low energy barrier through a biradicaloid transition state. Inversion is primarily driven by the release of strain associated with steric hindrance at the peri position of the anthanthrone core; a low-lying diradical state is accessible through planarization of the core, which is attained in solution at moderate temperatures. The most significant aspect of this transformation is that planarization is also achieved by application of mild pressure in the solid state, wherein the diradical remains kinetically trapped. Complementary information from quantum chemistry, H NMR, and Raman spectroscopies, together with magnetic experiments, is consistent with the formation of a nanographene-like structure that possesses radical centers localized at the exo-anthanthrone carbons bearing phenyl substituents.

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