Enantiopure nanohoops through racemic resolution of diketo[n]CPPs by chiral derivatization as precursors to DBP[n]CPPs.
Daniel WassyMathias HermannJan S WössnerLucas FrédéricGrégory PietersBirgit EsserPublished in: Chemical science (2021)
Strained conjugated nanohoops are attractive synthetic targets due to the bending of their π-system, which leads to intriguing optoelectronic properties, among others. By incorporating non-mirror-symmetric aromatic panels, chiral nanohoops can be obtained. We herein present a strategy to enantiopure nanohoops by racemic resolution through chiral derivatization of diketone-embedded hoops. The resulting diketo[n]CPPs (n = 6, 7) contain two stereogenic carbon atoms each and possess high fluorescence quantum yields paired with circularly polarized luminescence. These are versatile precursors to chiral dibenzo[a,e]pentalene-based nanohoops DBP[n]CPPs with antiaromatic character and ambipolar electrochemical behavior. Due to their strained structures the DBP[n]CPPs do not racemize at room temperature, which is supported by high calculated isomerization barriers. X-ray crystallographic investigations on the DBP[n]CPPs and their precursors as well as DFT calculations provide insight into the build-up of strain energy during the synthetic transformations.
Keyphrases
- ionic liquid
- room temperature
- capillary electrophoresis
- single molecule
- ms ms
- high resolution
- density functional theory
- molecular dynamics
- energy transfer
- liquid chromatography tandem mass spectrometry
- gas chromatography mass spectrometry
- gold nanoparticles
- liquid chromatography
- mass spectrometry
- photodynamic therapy
- magnetic resonance imaging
- molecular docking
- molecular dynamics simulations
- monte carlo
- amino acid