New macrocycles with planar chirality-synthesis and determination of absolute configurations
Jarosław Kalisiak1, Paweł Skowronek, Jacek Gawroński
1Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
Abstract:
A versatile system for preparing macrocyclic compounds with planar chirality is presented. In this system chiral diazacoronands are synthesized readily from lariat-type diesters 13 and 14 and unsymmetrical diamines 7, 8, 12, 15, and 16 under non-high-dilution conditions. The title compounds were subjected to structural analysis by X-ray crystallography and circular dichroism spectroscopy, and absolute configurations for two representative examples (compounds 2 and 3) were assigned by molecular modeling. The correctness of the theoretical approach was verified by the crystallographic results obtained experimentally.
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