Pseudo-meta and pseudo-para diamino-octafluoro[2.2]paracyclophanes are challenging to separate either by chromatography or recrystallization, but through the use of a mixture of the two isomers, the (1)H, (19)F, and (13)C NMR spectra of these compounds have been fully and unambiguously assigned using (1)H COSY, (1)H-(19)F HOESY, (1)H-(13)C HSQC, (1)H-(13)C HMBC, and (19)F-(13)C HSQC techniques. This permits the easy identification of either of the individual isomers. In addition, the (13)C spectrum of the pseudo-ortho analogue is reported and assigned for the first time. The gem shift effect in this series of bridge-fluorinated paracyclophanes serves to deshield (1)H resonances and shield (13)C.
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http://dx.doi.org/10.1002/mrc.3882 | DOI Listing |
Nat Commun
August 2023
School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
Planar chiral [2.2]paracyclophane derivatives are a type of structurally intriguing and practically useful chiral molecules, which have found a range of important applications in the field of asymmetric catalysis and material science. However, access to enantioenriched [2.
View Article and Find Full Text PDFJ Am Chem Soc
September 2021
Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland.
Quantum interference (QI) of electron waves passing through a single-molecule junction provides a powerful means to influence its electrical properties. Here, we investigate the correlation between substitution pattern, conductance, and mechanosensitivity in [2.2]paracyclophane (PCP)-based molecular wires in a mechanically controlled break junction experiment.
View Article and Find Full Text PDFPolymers (Basel)
October 2018
Department of Applied Chemistry for Environment, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.
A novel π-stacked polymer based on a pseudo⁻⁻linked [2.2]paracyclophane moieties was synthesized by Sonogashira-Hagihara coupling. The UV-vis absorption spectra of the synthesized polymer and model compounds revealed an extension of the conjugation length owing to the through-space conjugation.
View Article and Find Full Text PDFJ Comput Chem
January 2016
Institut für Organische Chemie, Universität Würzburg, and Center for Nanosystems Chemistry, Am Hubland, 97074, Würzburg, Germany.
A series of paracyclophane (PC) bridged mixed-valence (MV) bis-triarylamine radical cations with different ([2.2], [3.3], [4.
View Article and Find Full Text PDFJ Org Chem
July 2014
Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Str. 1, D-53121 Bonn, Germany.
Despite the fact that functionalized planar chiral [2.2]paracyclophanes have received a lot of attention, the chemistry of pseudo-meta 4,15-distubstituted [2.2]paracyclophanes is largely unexplored.
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