Synthesis, characterization and supramolecular synthons in crystals of new derivatives of 10-oxa-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione

The molecules 1-5, having chiral centers, crystallize in centrosymmetric space groups as racemic compounds. In the solid state the association motifs of the imide fragments seem to be related to the structure (molecular shape and substituents) of the interacting molecules. The strongest interactions are the Nimide-H…Oimide/epoxy hydrogen bonds. They stabilize cyclic dimers (1,2), infinite chains (3,5) and other patterns (4) in crystal architecture. Additionally, in the crystals electrostatic interactions involving CO groups are observed; they form parallel (1) and anti-parallel (3,4) motifs.