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Updated: Jun 12, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Perylene bisimides with rigid 2,2'-biphenol bridges at bay area as conjugated chiral platforms
1Universität Würzburg, Institut für Organische Chemie and Röntgen Research Center for Complex Material Systems, Am Hubland, 97074 Würzburg, Germany.
Abstract:
Facile nucleophilic substitution of two chlorine atoms by 2,2'-biphenol at one of the two bay areas (1,12- and 6,7-positions) of core-tetrachlorinated perylene bisimide afforded a novel, completely desymmetrized perylene bisimide building block, which could be further functionalized by substitution of the remaining two chlorine atoms. The atropisomers (P- and M-enantiomers) of the core twisted perylene bisimides were resolved by HPLC on a chiral column at room temperature, and the activation parameters for racemization were elucidated.
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