AI Article Synopsis
- The study presents a novel quadruple helicene composed of two [6] and two [7]helicene moieties, involving 92 sp carbon atoms, synthesized through a single Scholl reaction.
- Chemical oxidation of this helicene yields a stable dication that maintains the same helicity across its four moieties, confirmed by single-crystal X-ray crystallography.
- The quadruple helicene displays unique optical properties with near-infrared absorption and emission peaks at 848 nm and 977 nm, along with distinct electronic circular dichroism in both near-infrared and visible-light regions.
Article Abstract
Herein, we report the synthesis, structural analysis, optical and chiroptical properties of a novel quadruple helicene, which has two [6] and two [7]helicene moieties fused in a contorted framework of 92 sp carbon atoms. It was synthesized by the Scholl reaction of a perylene-containing substrate with the formation of eight carbon-carbon bonds on the perylene unit in a single synthetic operation. Chemical oxidation of the quadruple helicene with tris(4-bromophenyl)ammoniumyl hexachloroantimonate resulted in an air-stable dication, which exhibits the same helicity in its four helicene moieties as unambiguously identified by single-crystal X-ray crystallography. The quadruple helicene exhibits unusual near-infrared absorption and emission with absorption and emission maxima at 848 nm and 977 nm, respectively, and its isolated enantiomers exhibit electronic circular dichroism in the near-infrared and visible-light regions.
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| http://dx.doi.org/10.1002/anie.202113203 | DOI Listing |
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