144526-35-2Relevant academic research and scientific papers
Synthesis and photophysics of new pyridyl end-capped 3D-dithia[3.3]paracyclophane-based Janus tectons: Surface-confined self-assembly of their model pedestal on HOPG
Attias, A.-J.,Auffray, M.,Charra, F.,Kreher, D.,Mathevet, F.,Sosa Vargas, L.
, p. 7665 - 7674 (2020/06/10)
Surface-confined supramolecular self-assembly is currently a promising strategy to create well-organised 2D-networks on conducting surfaces. However, using such substrates tends to quench any electronic properties of the adsorbed molecules. In this context, new pyridyl end-capped 3D-dithia[3.3]paracyclophane-based molecules were designed, along with their model compound (pedestal), with the objective of self-assembling these tectons on any substrate. The synthesis of these new molecules was not straightforward and is consequently described in detail. Once the materials were successfully isolated, their optoelectronic properties were investigated to study potential non-covalent interactions: through pH-dependent absorption and emission measurements, and infra-red spectrometry. We evidenced that both ionic bonding and coordination bonding are compatible with the molecules design. Finally, preliminary scanning tunneling microscopy (STM) studies were performed to study the supramolecular self-assembly properties of the model lower-deck (pedestal) on highly oriented pyrolytic graphite (HOPG): we observed a quasi-square lattice of self-assembled 2D-networks that appear to form independently of the underlying HOPG lattice.
Design and synthesis of a "molecular turnstile"
Bedard, Thomas C.,Moore, Jeffrey S.
, p. 10662 - 10671 (2007/10/03)
Macrobicycles 1-3 have been prepared by palladium-catalyzed double macrocyclization. The planar geometry of this system is such that the para axis of the inner ring exactly matches the inner diameter of the macrocycle. Molecular models suggest that the inner ring of 1 should be able to rotate freely about its long axis, acting like the spindle of a turnstile. For large spindle substituents, this rotation will become hindered while for intermediate sized substituents, a pair of energetically equivalent conformational states should rapidly interconvert on an experimentally observable time scale. Substituted derivatives 2 and 3 possess diastereotopic methylene protons which become operationally enantiotopic upon fast rotation. Based on variable-temperature 1H NMR and longitudinal T1 relaxation experiments, examples of what are believed to be freely rotating 2 and conformationally locked 3 spindles are reported. These molecules represent the first iteration in the development of phenylacetylene macrocycles possessing conformational bistability that may eventually lead to new types of solids or liquid crystals that respond rapidly to external electric fields.
